Serotonin Receptor Research Articles

Deprescribing Antidepressants in Children and Adolescents: A Systematic Review of Discontinuation Approaches, Cross-Titration, and Withdrawal Symptoms.

Background: Antidepressant medications, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), are commonly used to treat depressive, anxiety, and obsessive-compulsive disorders in youth. Yet, data on discontinuing these medications, withdrawal symptoms, and strategies to switch between them are limited. Methods: We searched PubMed and ClinicalTrials.gov through June 1, 2024, to identify randomized controlled trials assessing antidepressant discontinuation in youth. We summarized pediatric pharmacokinetic data to inform tapering and cross-titration strategies for antidepressants and synthesized these data with reports of antidepressant withdrawal. Results: Our search identified 528 published articles, of which 28 were included. In addition, 19 records were obtained through other methods, with 14 included. The corpus of records included 13 randomized, double-blind, placebo-controlled trials (3026 patients), including SSRIs (K = 10), SNRIs (K = 4), andTCAs (K = 1), ranging from 4 to 35 weeks. Deprescribing antidepressants requires considering clinical status, treatment response, and, in cross-titration cases, the pharmacokinetics and pharmacodynamics of both medications. Antidepressant withdrawal symptoms are related to the pharmacokinetics of the medication, which vary across antidepressants and may include irritability, palpitations, anxiety, nausea, sweating, headaches, insomnia, paresthesia, and dizziness. These symptoms putatively involve changes in serotonin transporter expression and receptor sensitivity, impacting the serotonin, dopamine, and norepinephrine pathways. Conclusions: Although approaches to deprescribing antidepressants in pediatric patients are frequently empirically guided, accumulating data related to the course of relapse and withdrawal symptoms, as well as the pharmacokinetic and pharmacodynamic properties of medications, should inform these approaches. Recommendations within this review support data-informed discussions of deprescribing-including when and how-that are critically important in the clinician-family-patient relationship.

Vilazodone,aNovel SSRI Antidepressant with 5-HT1A Partial Agonist Properties: Diminished Potentiation of Chronic Oral Methylphenidate-Induced Dynorphin Expression in the Striatum in Adolescent Male Rats.

Selective serotonin reuptake inhibitor (SSRI) antidepressants such as fluoxetine are used in combination with the medical psychostimulant methylphenidate (Ritalin) in a variety of treatments in children and adults. Unintended co-exposure to these psychotropic medications also occurs in patients on SSRIs who abuse methylphenidate as a "cognitive enhancer" or recreational drug. Preclinical research shows that SSRIs such as fluoxetine when given in conjunction with methylphenidate potentiate addiction-related gene regulation by methylphenidate in the striatum, consistent with the known facilitatory role for serotonin in psychostimulant-induced neuronal and behavioral changes. Moreover, fluoxetine combined with methylphenidate also facilitated subsequent acquisition of cocaine self-administration in adolescent rats, suggesting an increased addiction liability for methylphenidate. In the present study, we investigated the impact of a novel SSRI, vilazodone, on methylphenidate-induced gene regulation in adolescent male rats. In contrast to prototypical SSRIs such as fluoxetine, vilazodone also acts as a partial 5-HT1A serotonin receptor agonist and is thus proposed to temper serotonin input to the striatum. We compared the effects of chronic treatment (4 weeks) with vilazodone (10mg/kg, twice daily) with those of fluoxetine (5mg/kg, twice daily) on striatal dynorphin expression induced by oral methylphenidate treatment (30/60mg/kg/day in drinking water, 8h access daily). Our results demonstrate that, in contrast to fluoxetine, vilazodone had minimal or no potentiating effects on methylphenidate-induced dynorphin expression. This diminished impact on gene regulation was seen throughout the striatum, including the nucleus accumbens, where increased dynorphin expression has previously been associated with various aspects of addiction. Our findings suggest that vilazodone may serve as a better adjunct SSRI with reduced addiction-facilitating properties.

Effects of Different Photoperiods on Peripheral 5-Hydroxytryptamine Metabolism, Breast Muscle Glucose Metabolism, and Myopathies in Broilers.

Background: There is a close relationship between breast muscle glucose metabolism, peripheral 5-hydroxytryptamine (5-HT), and myopathies in animals. Here, this study aimed to investigate the effects of different photoperiods on peripheral 5-HT metabolism, white striping (WS), and wooden breast (WB) in broilers. Methods: A total of 216 healthy 5-day-old (d) Arbor Acres (AA) male broilers were randomly assigned to 12L:12D, 18L:6D, and 24L:0D photoperiods for 4 weeks. Results: Compared with the 12L:12D photoperiod, we found the WB score in broilers was significantly increased in the 18L:6D and 24L:0D photoperiod at week 4 (p < 0.05). Muscle glycogen was significantly reduced (p < 0.05) and glycolysis was promoted in the breast muscles of broilers under the 18L:6D and 24L:0D photoperiods at week 2 and 4. Peripheral 5-HT concentrations, the mRNA expression of tryptophan hydroxylase 1 (TPH1) and serotonin transporter (SERT) in the cecal mucosa, and 5-hydroxytryptamine receptor 2A (5-HTR2A) mRNA expression in the breast muscle of broilers significantly up-regulated in the 18L:6D and 24L:0D photoperiod at week 2 and 4 (p < 0.05). Conclusions: Our findings revealed that extending the photoperiod improved the breast muscle growth rate, but up-regulated 5-HT synthesis and secretion to higher peripheral 5-HT, induced breast muscle glucose metabolism disorder, and increased WB incidence rates in broilers.

Design and Synthesis of Potential Multi-Target Antidepressants: Exploration of 1-(4-(7-Azaindole)-3,6-dihydropyridin-1-yl)alkyl-3-(1H-indol-3-yl)pyrrolidine-2,5-dione Derivatives with Affinity for the Serotonin Transporter

We describe the design, synthesis and structure–activity relationship of a novel series of 1-(4-(7-azaindole)-3,6-dihydropyridin-1-yl)alkyl-3-(1H-indol-3-yl)pyrrolidine-2,5-dione derivatives with combined effects on the serotonin (5-HT1A) and dopamine (D2) receptors and the serotonin (5-HT), noradrenaline (NA), and dopamine (DA) transporters as multi-target directed ligands for the treatment of depression. All of the tested compounds demonstrated good affinity for the serotonin transporter (SERT). Among them, compounds 11 and 4 emerged as the lead candidates because of their promising pharmacological profile based on in vitro studies. Compound 11 displayed a high affinity for the 5-HT1A (Ki = 128.0 nM) and D2 (Ki = 51.0 nM) receptors, and the SERT (Ki = 9.2 nM) and DAT (Ki = 288.0 nM) transporters, whereas compound 4 exhibited the most desirable binding profile to SERT/NET/DAT among the series: Ki = 47.0 nM/167.0 nM/43% inhibition at 1 µM. These results suggest that compounds 4 and 11 represent templates for the future development of multi-target antidepressant drugs.

Molecular Dynamics (MD) Simulations Provide Insights into the Activation Mechanisms of 5-HT2A Receptors

Recent breakthroughs in the determination of atomic resolution 3-D cryo-electron microscopy structures of membrane proteins present an unprecedented opportunity for drug discovery. Structure-based drug discovery utilizing in silico methods enables the study of dynamic connectivity of stable conformations induced by the drug in achieving its effect. With the ever-expanding computational power, simulations of this type reveal protein dynamics in the nano-, micro-, and even millisecond time scales. In the present study, aiming to characterize the protein dynamics of the 5HT2A receptor stimulated by ligands (agonist/antagonist), we performed 1 µs MD simulations on 5HT2A/DOI (agonist), 5HT2A/GSK215083 (antagonist), and 5HT2A (APO, no ligand) systems. The crystal structure of 5HT2A/zotepine (antagonist) (PDB: 6A94) was used to set up the simulation systems in a lipid bilayer environment. We found the monitoring of the ionic lock residue pair (R3.50-E6.30) of 5HT2A in MD simulations to be a good approximation of the effects of agonists (ionic lock breakage) or antagonists (ionic lock formation) on receptor activation. We further performed analyses of the MD trajectories, including Principal Component Analysis (PCA), hydrogen bond, salt bridge, and hydrophobic interaction network analyses, and correlation between residues to identify key elements of receptor activation. Our results suggest that in order to trigger receptor activation, DOI must interact with 5HT2A through residues V5.39, G5.42, S5.43, and S5.46 on TM5, inducing significant conformational changes in the backbone angles of G5.42 and S5.43. DOI also interacted with residues W6.48 (toggle switch) and F6.51 on TM6, causing major conformational shifts in the backbone angles of F6.44 and V6.45. These structural changes were transmitted to the intracellular ends of TM5, TM6, and ICL3, resulting in the breaking of the ionic lock and subsequent G protein activation. The studies could be helpful in future design of selective agonists/antagonists for various serotonin receptors (5HT1A, 5HT2A, 5HT2B, 5HT2C, and 5HT7) involved in detrimental disorders, such as addiction and schizophrenia.

Sertraline-Induced 5-HT Dysregulation in Mouse Cardiomyocytes and the Impact on Calcium Handling.

Selective serotonin reuptake inhibitors (SSRIs) are prescribed in 15% of pregnancies in the United States for depression. Maternal use of SSRIs has been linked to an increased risk of congenital heart defects, but the exact mechanism of pathogenesis is unknown. SSRIs, including sertraline, are permeable to the placenta and can produce direct fetal exposure. Previously, we have shown decreased cardiomyocyte proliferation, left ventricle size, and cardiac expression of the serotonin receptor 5-HT2B in offspring of mice exposed to the SSRI sertraline relative to offspring of saline-exposed mice. Using a mouse model of in utero plus neonatal sertraline exposure, we observed lengthened peak-to-peak time of calcium oscillation (saline 784 ±76 ms; sertraline 1121 ± 130 ms, p<0.001) and decreased expression of critical genes in calcium regulation. We also observed significant up-regulation of specific miRNAs that modulate serotonin signaling in neonatal cardiac tissues (Slc6a4: miR-223-5p, miR-92a-2-5p, miR-182-5p; Htr2a: miR-34b-5p, miR-182-5p; Htr2b: miR-223-5p, miR-92a-2-5p, miR-337-5p) (p<0.05) with corresponding levels of the target mRNAs down-regulated (Slc6a4 0.73 ± 0.05; Htr2a 0.67 ± 0.04; Htr2b 0.72 ± 0.03; all p< 0.01), resulting in decreased production of the cognate proteins. Adult mice at 10 weeks showed altered cardiac parameters including decreased heart rates in males (saline 683 ± 8 vs sertraline 666 ± 6 beats per minute, p< 0.05) and ejection fraction in females (saline 83.9 ± 0.6% vs sertraline 80.6 ± 1.1%, p<0.05). These findings raise the question if sertraline exposure during development may increase the potential risk for cardiac disease when subjected to stress.

Asiaticoside improves depressive-like behavior in mice with chronic unpredictable mild stress through modulation of the gut microbiota

BackgroundAsiaticoside, the main active ingredient of Centella asiatica, is a pentacyclic triterpenoid compound. Previous studies have suggested that asiaticoside possesses neuroprotective and anti-depressive properties, however, the mechanism of its anti-depressant action not fully understood. In recent years, a growing body of research on anti-depressants has focused on the microbiota-gut-brain axis, we noted that disruption of the gut microbial community structure and diversity can induce or exacerbate depression, which plays a key role in the regulation of depression.MethodsBehavioral experiments were conducted to detect depression-like behavior in mice through sucrose preference, forced swimming, and open field tests. Additionally, gut microbial composition and short-chain fatty acid (SCFA) levels in mouse feces were analyzed 16S rRNA sequencing and gas chromatography-mass spectrometry (GC-MS). Hippocampal brain-derived neurotrophic factor (BDNF) and 5-hydroxytryptamine receptor 1A (5-HT1A) expression in mice was assessed by western blotting. Changes in serum levels of inflammatory factors, neurotransmitters, and hormones were measured in mice using ELISA.ResultsThis study revealed that oral administration of asiaticoside significantly improved depression-like behavior in chronic unpredictable mild stress (CUMS) mice. It partially restored the gut microbial community structure in CUMS mice, altered SCFA metabolism, regulated the hypothalamic–pituitary–adrenal axis (HPA axis) and inflammatory factor levels, upregulated BDNF and 5-HT1A receptor protein expression, and increased serum serotonin (5-hydroxytryptamine, 5-HT) concentration. These findings reveal that asiaticoside exerts antidepressant effects via the microbiota-gut-brain axis.ConclusionsThese results suggested that asiaticoside exerts antidepressant effects through the microbiota-gut-brain axis in a CUMS mouse model.

Tegaserod Stimulates 5-HT4 Serotonin Receptors in the Isolated Human Atrium.

Tegaserod (1-{[(5-methoxy-1H-indol-3-yl)methyliden]amino}-3-pentylguanidine) is a potent agonist at human recombinant 5-HT4 serotonin receptors. Consequently, tegaserod is utilized in the treatment of bowel diseases. The objective of this study was to test the hypothesis that tegaserod stimulates human cardiac atrial 5-HT4-receptors via cyclic adenosine monophosphate (cAMP)-dependent pathways. Tegaserod exerted positive inotropic effects (PIEs) and positive chronotropic effects (PCEs) in isolated left and right atrial preparations, respectively, from mice with cardiac-specific overexpression of the human 5-HT4 serotonin receptor (5-HT4-TG) in a concentration- and time-dependent manner. However, no effect was observed in the hearts of littermates of wild-type mice (WT). Western blot analysis revealed that the expression of 5-HT4 receptors was significantly higher in 5-HT4-TG mice compared to WT mice. The specificity of the signal for the 5-HT4 receptor was confirmed by the absence of the signal in the hearts of 5-HT4 receptor knockout mice. Furthermore, tegaserod increased the force of contraction (at concentrations as low as 10 nM), reduced the time of tension relaxation, and increased the rate of tension development in isolated electrically stimulated (at a rate of 60 beats per minute) human right atrial preparations (HAPs, obtained during open-heart surgery) when administered alone. The potency and efficacy of tegaserod to raise the force of contraction were enhanced in the presence of cilostamide, a phosphodiesterase III inhibitor. The positive inotropic effect of tegaserod in HAPs was found to be attenuated by the 5-HT4 serotonin receptor antagonist GR 125487 (0.1 µM). The efficacy of tegaserod (10 µM) in raising the force of contraction in HAPs was less pronounced than that of serotonin (10 µM) or isoprenaline (1 µM). Tegaserod shifted the concentration-response curve of the force of contraction to serotonin to the right in HAPs, indicating that it is a partial agonist at 5-HT4 serotonin receptors in this model. We propose that the mechanism of action of tegaserod in HAPs involves cAMP-dependent phosphorylation of cardiac regulatory proteins.

Are pediatricians aware of the mysterious FPIES? Current diagnostic and treatment options. Case report

The prevalence of food allergies continues to grow steadily, and due to certain difficulties in diagnosing allergies not associated with immunoglobulin E, some conditions are little known. Such diagnosis-challenging diseases include food protein-induced enterocolitis syndrome (FPIES), a relatively low-prevalence disease most commonly occurring in early childhood but, in some cases, affecting adults as well. The pathogenesis of FPIES has not been reliably studied. FPIES is associated with elevated serum tryptase and release of pro-inflammatory cytokines, including interleukin-17. A characteristic symptom of FPIES is uncontrollable vomiting, which is probably triggered by the serotonin secreted by enterochromaffin cells, which activates the vagus nerve and the vomiting reflex, determining a good response of vomiting relief with ondansetron, a serotonin receptor antagonist. Changes in gut microbiota composition were also reported in FPIES. FPIES can lead to severe complications such as hypovolemic shock due to the rapid progression of symptoms and rapid dehydration, which often requires hospitalization of patients with acute FPIES. The provoking factors usually include products from the "big nine" allergens: cow's milk, eggs, gluten, soy, nuts, peanuts, fish, seafood, and sesame. FPIES can be acute or chronic; the manifestations slightly differ depending on the disease form. Laboratory diagnosis is difficult due to the lack of reliable biomarkers, and the diagnosis is established clinically and confirmed with an oral provocation test. The key treatment for FPIES is to eliminate the trigger protein from the diet, and depending on the severity of the disease, some patients may be allowed to consume a heat-treated allergen. The prognosis of FPIES is favorable: tolerance to the trigger product in most cases is developed within two years. Further studies are required to clarify the pathogenesis, prevalence, and treatment methods, with prospective follow-up of patients with a history of FPIES and the analysis of concurrent and subsequent diseases, including allergic conditions. The article presents two clinical cases of children diagnosed with FPIES.

Hepatotoxicity of antipsychotics: an exploratory pharmacoepidemiologic and pharmacodynamic study integrating FAERS data and in vitro receptor-binding affinities.

Antipsychotic psychopharmacotherapy is associated with the risk of drug-induced liver injury (DILI). However, understanding specific risk factors remains challenging due to limited data. This study investigates the relationship between receptor binding affinities and occupancies of antipsychotics and their associated hepatotoxic risks. A disproportionality analysis with calculation of the Reporting Odds Ratio (ROR) and the Information Component (IC) was conducted using data fromthe FDA Adverse Event Reporting System (FAERS) to identify signals related to the Standardised MedDRA Query "drug-related hepatic disorders", which served as a proxy for drug-induced hepatotoxicity. This was followed by a pharmacoepidemiologic-pharmacodynamic approach to investigate the relationship between the ROR and substance-related receptor binding affinities and occupancy, which was estimated based on in vitro receptor-binding profiles. Significant signals were identified for several antipsychotics, including chlorpromazine, loxapine, olanzapine, and quetiapine, with chlorpromazine and loxapine showing the highest RORs for DILI. Gender-specific analysis revealed a higher frequency of signals in female patients. Statistically significant negative correlations were identified between the ROR for drug-related hepatic disorders and the affinity for serotonin receptor 5-HT1A (r (17) = -0.68, p = 0.0012), while a positive correlation was observed for cholinergic receptors (r (17) = 0.46, p = 0.048). No significant correlations were found related to other receptors or drug properties. Our findings suggest that the serotonin and probably the cholinergic system may play a role in the development of DILI related to antipsychotic medications. The identification of antipsychotics with a higher association with DILI, such as chlorpromazine, underscores the need for careful monitoring in clinical practice. However, our findings need further longitudinal studies to confirm causality. A better understanding of the associations may inform clinical decision-making, particularly in patients with an increased susceptibility to liver damage.

GR113808, a serotonin receptor 4 antagonist, prevents high-fat-diet-induced obesity, fatty liver formation, and insulin resistance in C57BL/6J mice

BackgroundThe burden of nonalcoholic fatty liver disease is increasing, and limited therapeutic drugs are available for its treatment. Serotonin binds to approximately 14 serotonin receptors (HTR) and plays diverse roles in obesity and metabolic complications. In this study, we focused on the function of HTR4 on nonalcoholic fatty liver disease using GR113808, a selective HTR4 antagonist.MethodsMale C57BL/6J mice were fed high-fat diet for 12 weeks with intraperitoneal GR113808 injection, and HTR expression, weight changes, glucose and lipid metabolism, hepatic fat accumulation, changes in adipose tissue, the changes in transcriptional factors of signaling pathways, and inflammations were assessed. Hep3B cells and 3T3-L1 cells were treated with siRNA targeting HTR4 to downregulate its expression and then cultured with palmitate to mimic a high-fat diet. The changes in transcriptional factors of signaling pathways, and inflammations were assessed in those cells.ResultsAfter feeding a high-fat diet to male C57BL/6J mice, HTR4 expression in the liver and adipose tissues decreased. GR113808 suppressed body weight gain and improved glucose intolerance. Furthermore, GR113808 not only decreased fatty liver formation but also reduced adipose tissue size. Additionally, GR113808 reduced inflammatory cytokine serum levels and inflammasome complex formation in both tissues. Palmitate treatment in HTR4-downregulated Hep3B cells, also reduced peroxisome proliferator-activated receptor γ and sterol regulatory element-binding protein-1 pathway induction as well as inflammasome complex formation, thus decreasing inflammatory cytokine levels. HTR4 downregulation in 3T3-L1 cells also reduced palmitate-induced inflammasome complex formation and inflammatory cytokine production. Palmitate-induced insulin resistance in Hep3B cells, but not in 3T3-L1 cells, was improved by HTR4 downregulation.ConclusionsIn summary, GR113808 protected against fatty liver formation and improved inflammation in the liver and adipose tissue. Downregulation of HTR4 ameliorated insulin resistance in the liver. These results suggest that HTR4 could serve as a promising therapeutic target for metabolic diseases.

Gray matter volume differences based on sex in first-episode drug-naive patients with major depressive disorder and its molecular analysis.

This study analyzed whether gray matter volume (GMV) differences exist between the sexes in patients with major depressive disorder (MDD) and explored the relationships between these differences and neurotransmitter systems. This study enrolled 190 first-episode drug-naive patients with MDD and 293 healthy controls. All participants underwent T1-weighted high-resolution MRI. The interaction between the diagnosis (healthy controls vs. MDD) and sex (male vs. female) regarding GMV alterations was analyzed. The JuSpace toolbox, which covers a wide range of neurotransmitter systems, was used to identify the relationship between MDD-induced and sex-induced GMV alterations and specific receptor/transporter proteins in the brain. Sex-specific GMV differences were observed in the healthy controls but not in MDD patients. Male healthy controls had a larger GMV in the bilateral parahippocampal, lingual, inferior occipital, fusiform, cerebellar subregions, and left inferior temporal than female healthy controls, but several subregions of the thalamus had a larger GMV in female healthy controls than in male healthy controls. Sex-induced GMV alterations were associated with 5-hydroxytryptamine receptor subtype 1a, cannabinoid receptor, and dopamine receptor (P < 0.01, false discovery rate corrected). GMV differences were not detected in the main effect of diagnosis and the interaction of diagnosis and sex. Sex-specific GMV differences are associated with the spatial distribution of serotonin, dopamine, and cannabinoid neurotransmitter receptor systems. Sex-based physiological differences in the GMV may account for male and female susceptibility to and differences in the clinical symptoms of MDD.

Classics in Chemical Neuroscience: Tianeptine.

Tianeptine (1) is an unusual antidepressant in that its mechanism of action appears to be independent from any activity at serotonin receptors or monoamine transporters. In fact, tianeptine has been shown to be a moderately potent agonist for the mu opioid receptor (MOR) and to a lesser extent the delta opioid receptor (DOR). Additionally, tianeptine's efficacy may be related to its action on glutamate-mediated pathways of neuroplasticity. Regardless of which neurotransmitter system is primarily responsible for the observed efficacy, the MOR agonist activity is problematic with respect to abuse liability. Increasing numbers of case reports have demonstrated that tianeptine is indeed being used recreationally at doses far beyond what are considered therapeutically relevant or safe, and scheduling reclassifications or outright bans on tianeptine products are ongoing around the world. It is the aim of this review to discuss the medicinal chemistry and pharmacology of tianeptine and to summarize this intriguing discrepancy between tianeptine's historical use as a safe and effective antidepressant and its emerging potential for abuse.

Concerted modulation of spontaneous behavior and time-integrated whole-brain neuronal activity by serotonin receptors.

Serotonin neurons from the raphe nuclei project across the entire brain and modulate diverse physiology and behavior by acting on over a dozen receptors. Here, we took a step towards dissecting this complex process by examining the effects of agonists and antagonists of four widely expressed serotonin receptors (2A, 2C, 1A, and 1B) on spontaneous mouse behavior, which we related to time-integrated whole-brain neuronal activity as assessed by the expression of Fos, a canonical immediate-early gene product. Low-dimensional representations of behavioral and Fos map data revealed the dominant factors of variation in each domain, captured predictable differences across drug groups, and enabled predictions of behavioral changes following perturbations in Fos maps and vice versa. Our study provides a rich resource describing the effects of manipulating serotonin receptors on animal behavior and whole-brain integrated neuronal activity. It also establishes an experimental and analysis paradigm for interrogating the relationship between behavior and neuronal activity across different time scales.

The association between the serotonin receptor gene and anxiety as a factor in human adaptation to extreme conditions in Yakutia

This study investigates the genetic predisposition to anxiety and its impact on adaptation to the extreme conditions of the North-East region of Russia, particularly concerning the Yakut population. Special attention was given to the polymorphism of the serotonin receptor gene HTR2A (rs6311) and its association with levels of situational anxiety (SA) and personal anxiety (PA). The study involved 261 Yakuts (n = 261) who are permanently residing in Yakutia, do not exhibit any psychoneurological symptoms, and provided voluntary informed consent. Anxiety level was assessed using the Spielberger-Khanin scale. Genotyping was performed using PCR and RFLP, followed by detection through electrophoresis in an agarose gel. The findings indicate that the sample was characterized by a predominance of individuals with moderate levels of SA (60.9 %) and PA (57.5 %). However, in the group of women, individuals exhibited a high level of PA (53.8 %). The highest percentage of agreement in anxiety levels (69.7 %) was observed among individuals with moderate SA and PA. Given that the serotonergic system is involved in regulating behavior, emotions, and various physiological functions, and plays a crucial role in mitigating the negative behavioral consequences of stressors, a study on the polymorphism of the serotonin receptor gene HTR2A (rs6311) was conducted. The analysis of the distribution characteristics of the genotypes and alleles associated with the polymorphism of the serotonin receptor gene HTR2A (rs6311) in the Yakut population revealed a significant predominance of carriers with the homozygous genotype GG (60.2 %), and the G allele (0.782). Futhermore, when examining the distribution of allelic variants of the studied polymorphism based on the level and type of anxiety, it was observed that the AG and GG genotypes were more prevalent among individuals with high PA and low SA. These results confirm the significance of genetic factors in adaptation to the extreme conditions of the North.

8429 Serotonin Receptor Antagonist Alleviates Vascular Defects Produced by Selective Serotonin Reuptake Inhibitor Treatment During Gestation

Abstract Disclosure: L.P. Agnew: None. R. Domingues: None. A. Weichmann: None. L.L. Hernandez: None. Maternal mental health is critical for both mother and infant and often antidepressant therapy outweighs the potential risks of selective serotonin reuptake inhibitor (SSRI) treatment; however, SSRI use is associated with adverse neonatal outcomes. Preliminary work in our laboratory revealed placental apoptosis in pregnant dams treated with fluoxetine (FLX) and dams genetically deficient for the serotonin transporter gene. We hypothesize that SSRIs decrease placental blood flow, causing apoptosis and organ death via signaling through the serotonin 2A/2C receptors. Pregnant female C57BL6 mice were randomized to be treated daily, via I.P. injection, from E10-17.5 with saline (CON; n=6), 2 mg/kg FLX (n=5), or 2 mg/kg ketanserin plus 2 mg/kg FLX (n=5). On E17.5, using high-resolution ultrasound imaging, we identified the uterine artery, individual umbilical cords, and placental disc blood vessels. We calculated blood pressure, blood volume, blood flow rate, and heart rate in the uterine artery, umbilical cord, and placental disc. FLX (decreased blood volume in the uterine artery compared to ketanserin plus FLX (48.42 ± 18.26, 116.54 ± 45.25; p=0.0077), and decreased average (89.38 ± 31.50) and peak (130.36 ± 39.05) blood velocity in the uterine artery compared to ketanserin plus FLX average (162.76 ± 68.46; p=0.0322) and peak (236.77 ± 92.43; p=0.0242) blood velocity. FLX decreased average (0.04 + 0.02) and peak (0.07 ± 0.04) blood pressure in the uterine artery compared to ketanserin and FLX treated animals average (0.12 ± 0.10; p=0.0634) and peak (0.25 ± 0.19; p=0.0412) blood pressure. Ketanserin plus FLX (391 ± 38.29) decreased heart rate (BPM) in the placental disc compared to untreated controls (450.67 ± 26.08; p=0.0128). In the umbilical cord, ketanserin plus FLX (393 ± 28.25) decreased BPM compared to CON (450.17 ± 29.44; p=0.0078) and compared to FLX treatment alone (437.20 ± 17.28; p=0.0450). FLX treatment of dams during pregnancy reduces blood flow volume, heart rate, and blood flow velocity to the placenta via the uterine artery. The use of ketanserin, an inhibitor of serotonin receptor 2A/2C signaling, in combination with FLX, reduced the effects of FLX on the uterine artery. These data suggest that treatment with ketanserin could be utilized to alleviate the reproductive side effects of antidepressant usage for pregnant mothers while allowing the mother to remain on antidepressants. Future research should further investigate the effects of SSRI and ketanserin on blood flow to the fetus through the umbilical cord. Presentation: 6/2/2024

8429 Serotonin Receptor Antagonist Alleviates Vascular Defects Produced by Selective Serotonin Reuptake Inhibitor Treatment During Gestation

Abstract Disclosure: L.P. Agnew: None. R. Domingues: None. A. Weichmann: None. L.L. Hernandez: None. Maternal mental health is critical for both mother and infant and often antidepressant therapy outweighs the potential risks of selective serotonin reuptake inhibitor (SSRI) treatment; however, SSRI use is associated with adverse neonatal outcomes. Preliminary work in our laboratory revealed placental apoptosis in pregnant dams treated with fluoxetine (FLX) and dams genetically deficient for the serotonin transporter gene. We hypothesize that SSRIs decrease placental blood flow, causing apoptosis and organ death via signaling through the serotonin 2A/2C receptors. Pregnant female C57BL6 mice were randomized to be treated daily, via I.P. injection, from E10-17.5 with saline (CON; n=6), 2 mg/kg FLX (n=5), or 2 mg/kg ketanserin plus 2 mg/kg FLX (n=5). On E17.5, using high-resolution ultrasound imaging, we identified the uterine artery, individual umbilical cords, and placental disc blood vessels. We calculated blood pressure, blood volume, blood flow rate, and heart rate in the uterine artery, umbilical cord, and placental disc. FLX (decreased blood volume in the uterine artery compared to ketanserin plus FLX (48.42 ± 18.26, 116.54 ± 45.25; p=0.0077), and decreased average (89.38 ± 31.50) and peak (130.36 ± 39.05) blood velocity in the uterine artery compared to ketanserin plus FLX average (162.76 ± 68.46; p=0.0322) and peak (236.77 ± 92.43; p=0.0242) blood velocity. FLX decreased average (0.04 + 0.02) and peak (0.07 ± 0.04) blood pressure in the uterine artery compared to ketanserin and FLX treated animals average (0.12 ± 0.10; p=0.0634) and peak (0.25 ± 0.19; p=0.0412) blood pressure. Ketanserin plus FLX (391 ± 38.29) decreased heart rate (BPM) in the placental disc compared to untreated controls (450.67 ± 26.08; p=0.0128). In the umbilical cord, ketanserin plus FLX (393 ± 28.25) decreased BPM compared to CON (450.17 ± 29.44; p=0.0078) and compared to FLX treatment alone (437.20 ± 17.28; p=0.0450). FLX treatment of dams during pregnancy reduces blood flow volume, heart rate, and blood flow velocity to the placenta via the uterine artery. The use of ketanserin, an inhibitor of serotonin receptor 2A/2C signaling, in combination with FLX, reduced the effects of FLX on the uterine artery. These data suggest that treatment with ketanserin could be utilized to alleviate the reproductive side effects of antidepressant usage for pregnant mothers while allowing the mother to remain on antidepressants. Future research should further investigate the effects of SSRI and ketanserin on blood flow to the fetus through the umbilical cord. Presentation: 6/2/2024

The serotonin 1A receptor promoter polymorphism, rs6295, is associated with morphofunctional features

Introduction. The tendency to weight gain is influenced by many genetic and environmental factors (nutrition, level of physical activity, social well-being, etc.), as well as complex interactions of these factors. Studying the genetic factors of obesity can help in developing individual strategies for the prevention and treatment of this common disease. One of the most important hereditary factors is the neurotransmitter systems gene polymorphism, (including the serotonin system gene polymorphism). The aim of the investigation is to study the associations of single nucleotide polymorphism of the rs6295 locus of the serotonin receptor gene 1A HTR1A with morphofunctional features and body weight gain. Material and methods. The study used the materials of a comprehensive anthropogenetic examination of 386 men and 418 women aged 17 to 30 years. More than 20 morphofunctional indicators were measured using the traditional anthropometric method. The material for genetic analysis was genomic DNA isolated from buccal epithelium. The reliability of intergroup differences was assessed using the Mann-Whitney criterion, while canonical discriminant analysis was used to study intergroup variability. Results. For the first time, a significant correlation was shown between the polymorphism of the serotonin receptor type 1 gene HTR1A and morphofunctional features: individuals with the G/G genotype with greater body weight have lower (compared to carriers of the C/C and C/G genotypes) values of the indicators of the level of metabolic processes and specific metabolism. Conclusion. The statistically significant obtained results may be used in the development of individual strategies for the prevention and treatment of obesity, and also allow us to supplement the information on the association of serotonin system gene polymorphism with morphofunctional features and contribute to expanding our understanding of the human physique features formation and their relationships with hereditary predisposition.

Development of a disulfidptosis-related prognostic model for endometrial cancer with potential therapeutic target

Prognosis biomarkers for endometrial cancer (EC) are in need. Recent evidence demonstrated the critical role of disulfidptosis, a novel cell death modality, in cancer. However, limited studies have developed a disulfidptosis-related gene model for EC. Disulfidptosis prognosis score of EC (disulfidptosis-PSEC) were constructed using disulfidptosis-related differently expression genes with the RNA data of 544 EC patients from The Cancer Genome Atlas (TCGA) dataset. Model was evaluated using time-dependent receiver operating characteristic curve analysis for overall survival (OS) and disease-free survival (DFS), along with the hazard ratio (HR) between risk groups. Then, the cellular and molecular profile for different risk groups were performed, along with drug target inference. Disulfidptosis-PSEC demonstrated outstanding prognostic value for OS and DFS, with 5-year area under curve of 0.71 (95% CI, 0.58–0.75) and 0.69 (95% CI, 0.62–0.76), respectively. Low risk group demonstrated better survival with an HR of 0.38 (95% CI, 0.24–0.59) and 0.46 (95% CI, 0.32–0.66) for OS and DFS, respectively. The model was independent of TCGA subtype. Low risk group were featured with more immune cell infiltration and less gene mutation. Serval drug targets, and the therapeutic value of serotonin receptor among copy number (CN)-low subpopulation, were identified. Disulfidptosis-PSEC was a potential prognosis biomarker for EC with targetable biological process.

Automated multimodal imaging of Caenorhabditis elegans behavior in multi-well plates.

Assays of behavior in model organisms play an important role in genetic screens, drug testing, and the elucidation of gene-behavior relationships. We have developed an automated, high-throughput imaging and analysis method for assaying behaviors of the nematode C. elegans. We use high-resolution optical imaging to longitudinally record the behaviors of 96 animals at a time in multi-well plates, and computer vision software to quantify the animals' locomotor activity, behavioral states, and egg laying events. To demonstrate the capabilities of our system we used it to examine the role of serotonin in C. elegans behavior. We found that egg-laying events are preceded by a period of reduced locomotion, and that this decline in movement requires serotonin signaling. In addition, we identified novel roles of serotonin receptors SER-1 and SER-7 in regulating the effects of serotonin on egg laying across roaming, dwelling, and quiescent locomotor states. Our system will be useful for performing genetic or chemical screens for modulators of behavior.