The atypical antidepressant and neurorestorative agent tianeptine is a μ-opioid receptor agonist

3,3-Dibromoflavanone, a synthetic flavonoid derivative for pain management with antidepressant-like effects and fewer side effects than those of morphine in mice

In the pursuit of new lead compounds with fewer side effects than opioids, the novel synthetic phytochemical core, 3,3-dibromoflavanone (3,3-DBF), has emerged as a promising candidate for pain management. Acute assays demonstrated dose-dependent central and peripheral antinociceptive activity of 3,3-DBF through the μ-opioid receptor. This study aimed to explore repeated administration effects of 3,3-DBF in mice and compare them with morphine. Mice were treated with 3,3-DBF (30 mg/kg), morphine (6 mg/kg), or vehicle for 10 days, alongside single-treatment groups. Unlike morphine, 3,3-DBF demonstrated antinociceptive effects in the hot plate test without inducing tolerance. Locomotor activity and motor coordination tests (evaluated through the inverted screen and rotarod tests) revealed no significant differences between the 3,3-DBF-treated and control groups. The gastrointestinal transit assay indicated that 3,3-DBF did not induce constipation, in contrast to morphine. Furthermore, withdrawal signs assessed with the Gellert-Holtzman scale were not comparable to morphine. Additionally, 3,3-DBF exhibited antidepressant-like activity, reducing immobility time in the forced swimming and tail suspension tests, akin to imipramine. In summary, 3,3-DBF demonstrated antinociceptive effects without inducing tolerance or dependence and exhibited antidepressant properties. These findings highlight the potential of 3,3-DBF as a promising therapeutic agent for pain management and its comorbidities, offering advantages over morphine by minimizing side effects.

Interactions of antidepressants with concomitant medications-safety of complex therapies in multimorbidities

Depression is the fourth most serious disease in the world. Left untreated, it is a cause of suicide attempts, emergence or exacerbation worsening of serious diseases, bodily and mental disorders, as well as increased risk of cardiovascular diseases, stroke, diabetes, and obesity, as well as endocrine and neurological diseases. Frequent coexistence of depression and other diseases requires the simultaneous use of several drugs from different therapeutic groups, which very often interact and intensify comorbidities, sometimes unrelated mechanisms. Sufficient awareness of potential drug interactions is critical in clinical practice, as it allows both to avoid disruption of proper pharmacotherapy and achieve substantive results. Therefore, this review aims to analyze the interactions of antidepressants with other concomitant medications. Against the backdrop of experimental research and a thorough analysis of the up-to-date literature, the authors discuss in detail the mechanisms and effects of action of individual drug interactions and adaptogens, including the latest antidepressants.

The atypical antidepressant tianeptine confers neuroprotection against oxygen-glucose deprivation

Proregenerative and neuroprotective effects of antidepressants are an important topic of inquiry in neuropsychiatric research. Oxygen-glucose deprivation (OGD) mimics key aspects of ischemic injury in vitro. Here, we studied the effects of 24-h pretreatment with serotonin (5-HT), citalopram (CIT), fluoxetine (FLU), and tianeptine (TIA) on primary mouse cortical neurons subjected to transient OGD. 5-HT (50 μM) significantly enhanced neuron viability as measured by MTT assay and reduced cell death and LDH release. CIT (10 μM) and FLU (1 μM) did not increase the effects of 5-HT and neither antidepressant conferred neuroprotection in the absence of supplemental 5-HT in serum-free cell culture medium. By contrast, pre-treatment with TIA (10 μM) resulted in robust neuroprotection, even in the absence of 5-HT. Furthermore, TIA inhibited mRNA transcription of candidate genes related to cell death and hypoxia and attenuated lipid peroxidation, a hallmark of neuronal injury. Finally, deep RNA sequencing of primary neurons subjected to OGD demonstrated that OGD induces many pathways relating to cell survival, the inflammation-immune response, synaptic dysregulation and apoptosis, and that TIA pretreatment counteracted these effects of OGD. In conclusion, this study highlights the comparative strength of the 5-HT independent neuroprotective effects of TIA and identifies the molecular pathways involved.

Effects of Antidepressants on Sleep in Post-traumatic Stress Disorder: An Overview of Reviews

Antidepressants are a commonly used, easily accessible, and overall safe treatment option for post-traumatic stress disorder (PTSD). The present review aims to evaluate the efficacy and safety of antidepressants in treating sleep disturbances in patients with PTSD. PubMed and the Cochrane Library were searched (July 2022) for systematic reviews and meta-analyses on the treatment of PTSD. Moreover, PubMed and ClinicalTrials.gov were searched for individual trials investigating the antidepressant treatment of PTSD (up to September 2022), and reference lists of all possibly relevant identified studies were screened. Sleep-related outcomes, i.e., total sleep time, sleep quality, dreams/ nightmares, insomnia, and somnolence, were extracted independently by at least two reviewers. Metaanalytic evaluations were performed wherever possible. 39 randomised controlled trials (RCTs) were identified; data from pooled analyses, reviews, and observational studies were used for antidepressants with a weak evidence base or when their findings were deemed important. Overall, scarce data exist on the effects of antidepressants on sleep outcomes among patients with PTSD. Some evidence may support the use of amitriptyline, nefazodone, paroxetine, and sertraline for improving sleep in patients with PTSD. Τhere was a meta-analytical trend indicating improvement of nightmares with fluoxetine, less insomnia with amitriptyline and more with brofaromine, as well as more somnolence with paroxetine vs. placebo, respectively. However, data from more than 1 RCT with a considerable number of patients were only available for paroxetine. Evidence is insufficient to draw safe conclusions. More and better-designed RCTs, with consistent reporting of sleep-related outcomes, are needed.

Opioid Mechanisms and the Treatment of Depression

Opioid receptors are widely expressed in the brain, and the opioid system has a key role in modulating mood, reward processing and stress responsivity. There is mounting evidence that the endogenous opioid system may be dysregulated in depression and that drug treatments targeting mu, delta and kappa opioid receptors may show antidepressant potential. The mechanisms underlying the therapeutic effects of opioid system engagement are complex and likely multi-factorial. This chapter explores various pathways through which the modulation of the opioid system may influence depression. These include impacts on monoaminergic systems, the regulation of stress and the hypothalamic-pituitary-adrenal axis, the immune system and inflammation, brain-derived neurotrophic factors, neurogenesis and neuroplasticity, social pain and social reward, as well as expectancy and placebo effects. A greater understanding of the diverse mechanisms through which opioid system modulation may improve depressive symptoms could ultimately aid in the development of safe and effective alternative treatments for individuals with difficult-to-treat depression.

Neonatal Opioid Withdrawal Syndrome Following Prenatal Use of Supplements Containing Tianeptine

Tianeptine is an opioid receptor agonist that is prescribed as an antidepressant in many countries. In the United States, tianeptine is not approved for medical use because of its potential for abuse and addiction. Nonetheless, products containing tianeptine are easily obtainable and are marketed as dietary supplements. There are increasing reports of adverse effects and fatal toxicities resulting from tianeptine use among adolescents and adults. This emerging public health threat could escalate the opioid epidemic and drive increased newborn perinatal exposure. The impact of in utero exposure to tianeptine has not been studied, and to our knowledge, the authors of only 1 report have documented possible neonatal effects. Here, we describe a case of chronic prenatal exposure to tianeptine in the setting of maternal dependence on dietary supplements. This infant developed signs of severe withdrawal shortly after birth that were refractory to treatment with oral phenobarbital but responded to subsequent oral morphine therapy. On further questioning, the mother revealed the use of a tianeptine-containing dietary supplement. We did not perform confirmatory toxicology testing because tianeptine is not assayed by usual urine drug screening tests. For infants with clinical signs of opioid withdrawal without known etiology, we suggest that the maternal interview should inquire about the use of neurotropic over-the-counter drugs.

Assessment of the potential of novel and classical opioids to induce respiratory depression in mice

BACKGROUND AND PURPOSE

Opioid-induced respiratory depression limits the use of μ-opioid receptor agonists in clinical settings and is the main cause of opioid overdose fatalities. The relative potential of different opioid agonists to induce respiratory depression at doses exceeding those producing analgesia is understudied despite its relevance to assessments of opioid safety. Here we evaluated the respiratory depressant and anti-nociceptive effects of three novel opioids and relate these measurements to their in vitro efficacy.

EXPERIMENTAL APPROACH

Respiration was measured in awake, freely moving male CD-1 mice using whole body plethysmography. Anti-nociception was measured using the hot plate test. Morphine, oliceridine and tianeptine were administered intraperitoneally, whereas methadone, oxycodone and SR-17018 were administered orally. Receptor activation and arrestin-3 recruitment were measured in HEK293 cells using BRET assays.

KEY RESULTS

Across the dose ranges examined, all opioids studied depressed respiration in a dose-dependent manner, with similar effects at the highest doses, and with tianeptine and oliceridine showing reduced duration of effect, when compared with morphine, oxycodone, methadone and SR-17018. When administered at doses that induced similar respiratory depression, all opioids induced similar anti-nociception, with tianeptine and oliceridine again showing reduced duration of effect. These data were consistent with the in vitro agonist activity of the tested compounds.

CONCLUSION AND IMPLICATIONS

In addition to providing effective anti-nociception, the novel opioids, oliceridine, tianeptine and SR-17018 depress respiration in male mice. However, the different potencies and kinetics of effect between these novel opioids may be relevant to their therapeutic application in different clinical settings.

"Tianeptine abuse via novel, extended-release, star-shaped, drug delivery device"

We report a rare domestic case of exposure to tianeptine and use of a novel, extended-release, six-armed, star-shaped, drug delivery capsule. A 40-year-old male with a history of depression, anxiety, ethanol, opioid, cannabis, and tobacco use disorders presented to the emergency department (ED) from a substance abuse residential recovery treatment program after developing hypertension, tachycardia, and tremor for two day. He used an extended-release, six-armed, star-shaped, drug delivery device he purchased online, filling each arm with 15 mg of tianeptine (90 mg total). His intention was to mitigate the symptoms of kratom/opioid withdrawal through this extended-release method while simultaneously undergoing formal treatment for ethanol withdrawal. Tianeptine is an atypical tricyclic antidepressant that exerts complex mechanisms of action including serotonin (5-HT) neuromodulation as well as full μ-opioid and ∂-opioid receptor agonism. The capsule itself is made of caprolactone, which is a bioabsorbable material similar to absorbable sutures, initially developed as a long-term enteral antimalarial delivery method and is not FDA approved for human use. Over the course of the patients two day hospitalization course he developed symptoms consistent with uncomplicated ethanol withdrawal, which were treated with as-needed phenobarbital. No clinical manifestations of opioid or serotonin toxicity developed. Serial EKGs and telemetry monitoring remained unchanged. The patient was then medically cleared and discharged back to the residential recovery treatment program.

Tianeptine promotes lasting antiallodynic effects in a mouse model of neuropathic pain

Tricyclic antidepressants (TCAs), such as desipramine (DMI), are effective at managing neuropathic pain symptoms but often take several weeks to become effective and also lead to considerable side effects. Tianeptine (TIAN) is an atypical antidepressant that activates the mu-opioid receptor but does not produce analgesic tolerance or withdrawal in mice, nor euphoria in humans, at clinically-relevant doses. Here, we evaluate the efficacy of TIAN at persistently alleviating mechanical allodynia in the spared nerve injury (SNI) model of neuropathic pain, even well after drug clearance. After finding an accelerated onset of antiallodynic action compared to DMI, we used genetically modified mice to gain insight into RGS protein-associated pathways that modulate the efficacy of TIAN relative to DMI in models of neuropathic pain. Because we observed similar behavioral responses to both TIAN and DMI treatment in RGS4, RGSz1, and RGS9 knockout mice, we performed RNA sequencing on the NAc of TIAN- and DMI-treated mice after prolonged SNI to further clarify potential mechanisms underlying TIANs faster therapeutic actions. Our bioinformatic analysis revealed distinct transcriptomic signatures between the two drugs, with TIAN more directly reversing SNI-induced differentially expressed genes, and further predicted several upstream regulators that may be implicated in onset of action. This new understanding of the molecular pathways underlying TIAN action may enable the development of novel and more efficacious pharmacological approaches for the management of neuropathic pain.

Activation of σ1-Receptors by R-Ketamine May Enhance the Antidepressant Effect of S-Ketamine

Ketamine is a racemic mixture composed of two enantiomers, S-ketamine and R-ketamine. In preclinical studies, both enantiomers have exhibited antidepressant effects, but these effects are attributed to distinct pharmacological activities. The S-enantiomer acts as an NMDA-channel blocker and as an opioid μ-receptor agonist, whereas the R-enantiomer binds to σ1-receptors and is believed to act as an agonist. As racemate, ketamine potentially triggers four biochemical pathways involving the AGC-kinases, PKA, Akt (PKB), PKC and RSK that ultimately lead to inhibitory phosphorylation of GSK3β in microglia. In patients with major depressive disorder, S-ketamine administered as a nasal spray has shown clear antidepressant activity. However, when compared to intravenously infused racemic ketamine, the response rate, duration of action and anti-suicidal activity of S-ketamine appear to be less pronounced. The σ1-protein interacts with μ-opioid and TrkB-receptors, whereas in preclinical experiments σ1-agonists reduce μ-receptor desensitization and improve TrkB signal transduction. TrkB activation occurs as a response to NMDA blockade. So, the σ1-activity of R-ketamine may not only enhance two pathways via which S-ketamine produces an antidepressant response, but it furthermore provides an antidepressant activity in its own right. These two factors could explain the apparently superior antidepressant effect observed with racemic ketamine compared to S-ketamine alone.

Pharmacology of viable mechanism agnostic respiratory stimulants for the reversal of drug-induced respiratory depression in humans

INTRODUCTION

Drug-induced respiratory depression is potentially fatal and can be caused by various drugs such as synthetic opioids and tranquilizers. The only class of respiratory depressants that has a specific reversal agent are opioids, such as naloxone. These reversal agents have limited utility in situations of polysubstance ingestion with agents from multiple respiratory depressant classes. Hence, there is an unmet need for drugs that stimulate breathing irrespective of the underlying cause of respiratory depression, i.e. mechanism agnostic respiratory stimulants.

AREAS COVERED

In this review, we discuss agnostic respiratory stimulants, tested in humans with promising results, i.e. ampakines, drugs that act at the carotid bodies, N-methyl-D-aspartate receptor antagonist ketamine, and orexin receptor-2-agonist danavorexton, and others that demonstrated positive effects in animals but not yet in humans.

EXPERT OPINION

Rapid, effective rescuing of individuals who overdosed on respiratory depressants saves lives. While naloxone is the preferred drug for reversing opioid-induced respiratory depression, its effectiveness is limited in cases involving non-opioids. While several agnostic respiratory stimulants showed promise in humans, further research is needed to optimize dosing, evaluate safety and efficacy in deeper respiratory depression (apnea). Additionally, future studies should combine agnostic stimulants with naloxone, to improve rapid, effective rescue from drug overdoses.

Contribution of the opioid system to depression and to the therapeutic effects of classical antidepressants and ketamine

Major depressive disorder (MDD) afflicts approximately 5 % of the world population, and about 30-50 % of patients who receive classical antidepressant medications do not achieve complete remission (treatment resistant depressive patients). Emerging evidence suggests that targeting opioid receptors mu (MOP), kappa (KOP), delta (DOP), and the nociceptin/orphanin FQ receptor (NOP) may yield effective therapeutics for stress-related psychiatric disorders. As depression and pain exhibit significant overlap in their clinical manifestations and molecular mechanisms involved, it is not a surprise that opioids, historically used to alleviate pain, emerged as promising and effective therapeutic options in the treatment of depression. The opioid signaling is dysregulated in depression and numerous preclinical studies and clinical trials strongly suggest that opioid modulation can serve as either an adjuvant or even an alternative to classical monoaminergic antidepressants. Importantly, some classical antidepressants require the opioid receptor modulation to exert their antidepressant effects. Finally, ketamine, a well-known anesthetic whose extremely efficient antidepressant effects were recently discovered, was shown to mediate its antidepressant effects via the endogenous opioid system. Thus, although opioid system modulation is a promising therapeutical venue in the treatment of depression further research is warranted to fully understand the benefits and weaknesses of such approach.

Chronic tianeptine induces tolerance in analgesia and hyperlocomotion via mu-opioid receptor activation in mice

Introduction

Tianeptine is approved in some countries to treat depression and anxiety. In addition to its activity on serotonin and glutamate neurotransmission, tianeptine has been proven to be a mu-opioid receptor (MOR) agonist, but only a few preclinical studies have characterized the opioid-like behavioral effects of tianeptine.

Methods

In this study, we tested tianeptine activity on G protein activation using the [S35] GTPγS binding assay in brain tissue from MOR+/+ and MOR-/- mice. Then, to determine whether tianeptine behavioral responses are MOR-dependent, we characterized the analgesic, locomotor, and rewarding responses of tianeptine in MOR+/+ and MOR-/- mice using tail immersion, hot plate, locomotor, and conditioned place preference tests.

Results

Using the [S35] GTPγS binding assay, we found that tianeptine signaling is mediated by MOR in the brain with properties similar to those of DAMGO (a classic MOR agonist). Furthermore, we found that the MOR is necessary for tianeptine's analgesic (tail immersion and hot plate), locomotor, and rewarding (conditioned place preference) effects. Indeed, these behavioral effects could only be measured in MOR+/+ mice but not in MOR-/- mice. Additionally, chronic administration of tianeptine induced tolerance to its analgesic and hyperlocomotor effects.

Discussion

These findings suggest that tianeptine's opioid-like effects require MOR and that chronic use could lead to tolerance.

An update on potential pharmacotherapies for cognitive impairment in bipolar disorder

INTRODUCTION

Cognitive impairment is a core feature of bipolar disorder (BD) that impedes recovery by preventing the return to optimal socio-occupational functioning and reducing quality of life. Presently, there are no efficacious treatments for cognitive impairment in BD, but many pharmacological interventions are being considered as they have the potential to target the underlying pathophysiology of the disorder.

AREAS COVERED

This review summarizes the available evidence for pharmacological interventions for cognitive impairment in bipolar disorder. We searched PubMed, MedLine, and PsycInfo from inception to December 1^st, 2022. Traditional treatments, such as lithium, anticonvulsants (lamotrigine), antipsychotics (aripiprazole, asenapine, cariprazine, lurasidone, and olanzapine), antidepressants (vortioxetine, fluoxetine, and tianeptine) and psychostimulants (modafinil), and emerging interventions, such as acetylcholinesterase inhibitors (galantamine and donepezil), dopamine agonists (pramipexole), erythropoietin, glucocorticoid receptor antagonists (mifepristone), immune modulators (infliximab, minocycline and doxycycline), ketamine, metabolic agents (insulin, metformin, and liraglutide), probiotic supplements, and Withania somnifera are discussed.

EXPERT OPINION

The investigation of interventions for cognitive impairment in BD is a relatively under-researched area. In the past, methodological pitfalls in BD cognition trials have also been a critical limiting factor. Expanding on the existing literature and identifying novel pharmacological and non-pharmacological treatments for cognitive impairment in BD should be a priority.

Inhibition of Microglial GSK3β Activity Is Common to Different Kinds of Antidepressants: A Proposal for an In Vitro Screen to Detect Novel Antidepressant Principles

Depression is a major public health concern. Unfortunately, the present antidepressants often are insufficiently effective, whilst the discovery of more effective antidepressants has been extremely sluggish. The objective of this review was to combine the literature on depression with the pharmacology of antidepressant compounds, in order to formulate a conceivable pathophysiological process, allowing proposals how to accelerate the discovery process. Risk factors for depression initiate an infection-like inflammation in the brain that involves activation microglial Toll-like receptors and glycogen synthase kinase-3β (GSK3β). GSK3β activity alters the balance between two competing transcription factors, the pro-inflammatory/pro-oxidative transcription factor NFκB and the neuroprotective, anti-inflammatory and anti-oxidative transcription factor NRF2. The antidepressant activity of tricyclic antidepressants is assumed to involve activation of GS-coupled microglial receptors, raising intracellular cAMP levels and activation of protein kinase A (PKA). PKA and similar kinases inhibit the enzyme activity of GSK3β. Experimental antidepressant principles, including cannabinoid receptor-2 activation, opioid μ receptor agonists, 5HT2 agonists, valproate, ketamine and electrical stimulation of the Vagus nerve, all activate microglial pathways that result in GSK3β-inhibition. An in vitro screen for NRF2-activation in microglial cells with TLR-activated GSK3β activity, might therefore lead to the detection of totally novel antidepressant principles with, hopefully, an improved therapeutic efficacy.

Contribution of the Opioid System to the Antidepressant Effects of Fluoxetine

BACKGROUND

Selective serotonin reuptake inhibitors such as fluoxetine have a limited treatment efficacy. The mechanism by which some patients respond to fluoxetine while others do not remains poorly understood, limiting treatment effectiveness. We have found the opioid system to be involved in the responsiveness to fluoxetine treatment in a mouse model for anxiety- and depressive-like behavior.

METHODS

We analyzed gene expression changes in the dentate gyrus of mice chronically treated with corticosterone and fluoxetine. After identifying a subset of genes of interest, we studied their expression patterns in relation to treatment responsiveness. We further characterized their expression through in situ hybridization and the analysis of a single-cell RNA sequencing dataset. Finally, we behaviorally tested mu and delta opioid receptor knockout mice in the novelty suppressed feeding test and the forced swim test after chronic corticosterone and fluoxetine treatment.

RESULTS

Chronic fluoxetine treatment upregulates proenkephalin expression in the dentate gyrus, and this upregulation is associated with treatment responsiveness. The expression of several of the most significantly upregulated genes, including proenkephalin, is localized to an anatomically and transcriptionally specialized subgroup of mature granule cells in the dentate gyrus. We have also found that the delta opioid receptor contributes to some, but not all, of the behavioral effects of fluoxetine.

CONCLUSIONS

These data indicate that the opioid system is involved in the antidepressant effects of fluoxetine, and this effect may be mediated through the upregulation of proenkephalin in a subpopulation of mature granule cells.

The Opioid System in Depression

Opioid receptors are widely distributed throughout the brain and play an essential role in modulating aspects of human mood, reward, and well-being. Accumulating evidence indicates the endogenous opioid system is dysregulated in depression and that pharmacological modulators of mu, delta, and kappa opioid receptors hold potential for the treatment of depression. Here we review animal and clinical data, highlighting evidence to support: dysregulation of the opioid system in depression, evidence for opioidergic modulation of behavioural processes and brain regions associated with depression, and evidence for opioidergic modulation in antidepressant responses. We evaluate clinical trials that have examined the safety and efficacy of opioidergic agents in depression and consider how the opioid system may be involved in the effects of other treatments, including ketamine, that are currently understood to exert antidepressant effects through non-opioidergic actions. Finally, we explore key neurochemical and molecular mechanisms underlying the potential therapeutic effects of opioid system engagement, that together provides a rationale for further investigation into this relevant target in the treatment of depression.

Respiratory effects of the atypical tricyclic antidepressant tianeptine in human models of opioid-induced respiratory depression

BACKGROUND

Animal data suggest that the antidepressant and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor modulator tianeptine is able to prevent opioid-induced respiratory depression. We hypothesize that oral or intravenous tianeptine can effectively prevent or counteract opioid-induced respiratory depression in humans.

METHODS

Healthy male and female volunteers participated in two studies that had a randomized, double blind, placebo-controlled, crossover design. We first tested oral tianeptine (37.5, 50 and 100 mg, 8 subjects/group) pretreatment followed by induction of alfentanil-induced respiratory depression (alfentanil target concentration 100 ng/mL). Primary endpoint was ventilation at an extrapolated end-tidal carbon dioxide concentration of 55 mmHg (V̇E55). We next determined the ability of four subsequent and increasing infusions of intravenous tianeptine (target tianeptine plasma concentrations 400, 1,000, 1,500 and 2,000 ng/mL, each given over 15 min), to counteract remifentanil-induced respiratory depression in 15 volunteers. Ventilation was measured at isohypercpania (baseline ventilation 20 ± 2 L/min). Primary endpoint was minute ventilation during the 60 min of tianeptine versus placebo infusion.

RESULTS

Alfentanil reduced V̇E55 to 13.7 (95% CI 8.6-18.8) L/min following placebo pretreatment and to 17.9 (10.2-25.7) L/min following 50 mg tianeptine pretreatment (mean difference between treatments 4.2 (-11.5-3.0) L/min, p = 0.070). Intravenous tianeptine in the measured concentration range of 500 to 2,000 ng/ml did not stimulate ventilation but instead worsened remifentanil-induced respiratory depression: tianeptine 9.6 ± 0.8 L/min versus placebo 15.0 ± 0.9 L/min, mean difference 5.3 L/min, 95% CI 2.5-8.2 L/min; p = 0.001, after 1 hour of treatment.

CONCLUSIONS

Neither oral nor intravenous tianeptine were respiratory stimulants. Intravenous tianeptine over the concentration range of 500-2000 ng/mL worsened respiratory depression induced by remifentanil.

Opioid-like adverse effects of tianeptine in male rats and mice

RATIONALE

Tianeptine is a mu-opioid receptor (MOR) agonist with increasing reports of abuse in human populations. Preclinical data regarding the abuse potential and other opioid-like adverse effects of tianeptine at supratherapeutic doses are sparse.

OBJECTIVES

The present study evaluated tianeptine in a rat model of abuse potential assessment and in mouse models of motor, gastrointestinal, and respiratory adverse effects.

METHODS

Abuse potential was assessed in adult male Sprague-Dawley rats using an intracranial self-stimulation (ICSS) procedure to determine effects of acute and repeated tianeptine on responding for electrical brain stimulation. Male ICR mice were used to determine the effects of tianeptine in assays of locomotor behavior and gastrointestinal motility. Male Swiss-Webster mice were monitored for respiratory changes using whole-body plethysmography.

RESULTS

In rats, acute tianeptine produced weak and delayed evidence for abuse-related ICSS facilitation at an intermediate dose (10 mg/kg, IP) and pronounced, naltrexone-preventable ICSS depression at a higher dose (32 mg/kg, IP). Repeated 7-day tianeptine (10 and 32 mg/kg/day, IP) produced no increase in abuse-related ICSS facilitation, only modest tolerance to ICSS depression, and no evidence of physical dependence. In mice, tianeptine produced dose-dependent, naltrexone-preventable locomotor activation. Tianeptine (100 mg/kg, SC) also significantly inhibited gastrointestinal motility and produced naloxone-reversible respiratory depression.

CONCLUSIONS

Tianeptine presents as a MOR agonist with resistance to tolerance and dependence in our ICSS assay in rats, and it has lower abuse potential by this metric than many commonly abused opioids. Nonetheless, tianeptine produces MOR agonist-like acute adverse effects that include motor impairment, constipation, and respiratory depression.

Microdose Induction of Buprenorphine in a Patient Using Tianeptine

BACKGROUND

Opioids and opioid alternatives are a serious threat to public health in the United States and other countries. Patients are looking to the internet increasingly as a source of opioid alternatives to self-treat addiction or other psychiatric conditions. It is imperative that patients receive proper treatment to prevent morbidity and mortality related to opioid use disorder.

CASE SUMMARY

We report a case of a middle-aged male with a 3-year history of tianeptine use who presented to an outpatient clinic looking for addiction treatment options after failed attempts at tapering his daily dosage of approximately 10 grams per day. The patient underwent a microdose induction of sublingual buprenorphine over a 7-day period (0.25-12 mg) while continuing tianeptine use, and self-monitored for withdrawal symptoms daily using the Clinical Opiate Withdrawal Scale. The patient was seen over the course of treatment by a board-certified toxicologist and addiction specialist on day 2, 5, 6, and 14 to ensure patient safety and treatment adherence. After 14 days of treatment, the patient was able to stop tianeptine use without any major symptoms of withdrawal, anxiety, or depression.

DISCUSSION

This case report highlights the effectiveness of buprenorphine in the treatment of opioid use disorder in a patient using tianeptine and further exemplifies the utility of buprenorphine in an outpatient setting.

Effects of Tianeptine Treatment on Depression and Cognitive Function in Patients with Alzheimer’s Disease: A 12-Month Retrospective Observational Study

Background:

Depression is a common manifestation in Alzheimer’s disease (AD). In clinical practice, antidepressant medication is often used for depression in AD.

Objective:

We explore the effectiveness of the atypical antidepressant tianeptine compared with other conventional antidepressants in AD patients with depression in a real-life setting.

Methods:

We retrospectively identified 126 AD patients who had received antidepressant treatment for 12 months with tianeptine or other antidepressants. Subjects were divided into two groups according to the treatment they had received: tianeptine group (n = 38) or other antidepressant group (n = 88). Drug effects on depression, cognition, behavior, and functional performance were evaluated at baseline, 6, and 12 months. A Mixed Effects Model Analysis was carried out to evaluate changes in performance scores.

Results:

Both tianeptine and other antidepressants showed an antidepressant effect after 12 months with significant improvement on the Cornell Scale for Depression in Dementia, the Hamilton Depression Rating Scale, and the Neuropsychiatric Inventory-Depression subscale. A statistically significant improvement at 12 months was shown in the tianeptine group versus the other antidepressants group on most of the cognitive measures such as the Mini-Mental State Examination, the Letter and Category Fluency Test, the Rey Auditory Verbal Learning Test, and the Boston Naming Test.

Conclusion:

Our results suggest that tianeptine reduces depressive symptoms and improves cognition in AD patients. This could be considered clinically relevant and should inspire the design of future long-term randomized controlled trials that contribute to supporting the use of tianeptine for improving cognitive function in AD patients.

Mu opioid receptors on hippocampal GABAergic interneurons are critical for the antidepressant effects of tianeptine

Tianeptine is an atypical antidepressant used in Europe to treat patients who respond poorly to selective serotonin reuptake inhibitors (SSRIs). The recent discovery that tianeptine is a mu opioid receptor (MOR) agonist has provided a potential avenue for expanding our understanding of antidepressant treatment beyond the monoamine hypothesis. Thus, our studies aim to understand the neural circuits underlying tianeptine's antidepressant effects. We show that tianeptine induces rapid antidepressant-like effects in mice after as little as one week of treatment. Critically, we also demonstrate that tianeptine's mechanism of action is distinct from fluoxetine in two important aspects: (1) tianeptine requires MORs for its chronic antidepressant-like effect, while fluoxetine does not, and (2) unlike fluoxetine, tianeptine does not promote hippocampal neurogenesis. Using cell-type specific MOR knockouts we further show that MOR expression on GABAergic cells-specifically somatostatin-positive neurons-is necessary for the acute and chronic antidepressant-like responses to tianeptine. Using central infusion of tianeptine, we also implicate the ventral hippocampus as a potential site of antidepressant action. Moreover, we show a dissociation between the antidepressant-like phenotype and other opioid-like phenotypes resulting from acute tianeptine administration such as analgesia, conditioned place preference, and hyperlocomotion. Taken together, these results suggest a novel entry point for understanding what circuit dysregulations may occur in depression, as well as possible targets for the development of new classes of antidepressant drugs.

Reports of Adverse Events Associated with Use of Novel Psychoactive Substances, 2017-2020: A Review

An important role of modern forensic and clinical toxicologists is to monitor the adverse events of novel psychoactive substances (NPS). Following a prior review from 2013 to 2016, this critical literature review analyzes and evaluates published case reports for NPS from January 2017 through December 2020. The primary objective of this study is to assist in the assessment and interpretation of these cases as well as provide references for confirmation methods. Chemistry, pharmacology, adverse events and user profiles (e.g., polypharmacy) for NPS are provided including case history, clinical symptoms, autopsy findings and analytical results. Literature reviews were performed in PubMed and Google Scholar for publications using search terms such as NPS specific names, general terms (e.g., ‘designer drugs’ and ‘novel psychoactive substances’), drug classes (e.g., ‘designer stimulants’) and outcome-based terms (e.g., ‘overdose’ and ‘death’). Government and website drug surveillance databases and abstracts published by professional forensic science organizations were also searched. Toxicological data and detailed case information were extracted, tabulated, analyzed and organized by drug category. Case reports included overdose fatalities (378 cases), clinical treatment and hospitalization (771 cases) and driving under the influence of drugs (170 cases) for a total of 1,319 cases providing details of adverse events associated with NPS. Confirmed adverse events with associated toxidromes of more than 60 NPS were reported including synthetic cannabinoid, NPS stimulant, NPS hallucinogen, NPS benzodiazepine and NPS opioid cases. Fifty of these NPS were reported for the first time in January 2017 through December 2020 as compared to the previous 4 years surveyed. This study provides insight and context of case findings described in the literature and in digital government surveillance databases and websites during a recent 4-year period. This review will increase the awareness of adverse events associated with NPS use to better characterize international emerging drug threats.

Development of Dibenzothiazepine Derivatives as Multifunctional Compounds for Neuropathic Pain

Neuropathic pain is a chronic and sometimes intractable condition caused by lesions or diseases of the somatosensory nervous system. Many drugs are available but unfortunately do not provide satisfactory effects in patients, producing limited analgesia and undesirable side effects. Thus, there is an urgent need to develop new pharmaceutical agents to treat neuropathic pain. To date, highly specific agents that modulate a single target, such as receptors or ion channels, never progress to the clinic, which may reflect the diverse etiologies of neuropathic pain seen in the human patient population. Therefore, the development of multifunctional compounds exhibiting two or more pharmacological activities is an attractive strategy for addressing unmet medical needs for the treatment of neuropathic pain. To develop novel multifunctional compounds, key pharmacophores of currently used clinical pain drugs, including pregabalin, fluoxetine and serotonin analogs, were hybridized to the side chain of tianeptine, which has been used as an antidepressant. The biological activities of the hybrid analogs were evaluated at the human transporters of neurotransmitters, including serotonin (hSERT), norepinephrine (hNET) and dopamine (hDAT), as well as mu (μ) and kappa (κ) opioid receptors. The most advanced hybrid of these multifunctional compounds, 17, exhibited multiple transporter inhibitory activities for the uptake of neurotransmitters with IC₅₀ values of 70 nM, 154 nM and 2.01 μM at hSERT, hNET and hDAT, respectively. Additionally, compound 17 showed partial agonism (EC₅₀ = 384 nM) at the μ-opioid receptor with no influence at the κ-opioid receptor. In in vivo pain animal experiments, the multifunctional compound 17 showed significantly reduced allodynia in a spinal nerve ligation (SNL) model by intrathecal administration, indicating that multitargeted strategies in single therapy could considerably benefit patients with multifactorial diseases, such as pain.

Towards Tianeptine Analogues: Synthesis of New Ring Systems Containing a Dibenzo[c,f][1,2]thiazepine S,S-Dioxide Core

In the course of the synthesis of fused-ring analogues of the antidepressant drug tianeptine, representatives of three new heterocyclic ring systems, indolo[1,7-bc][1,2]benzothiazepines (and their 4,5-dihydro analogues), 5,6-dihydroquino[1,8-bc][1,2]benzothiazepines, and [1,2]benzothiazepino[4,3,2-jk]carbazoles, as well as their intermediates, have been prepared. The tetracyclic and pentacyclic ring systems containing either an oxo or a hydroxy functional group are suitable for introducing various side chains, including potential pharmacophores. For this latter transformation, examples are demonstrated by conversion of the hydroxy group into a chloro moiety and subsequent reaction with amines or with primary alcohols bearing a tertiary amino side chain. Two fused-ring derivatives exhibiting the side-chain characteristics of tianeptine have also been synthesized. Altogether 40 compounds are described in the present manuscript, eight of them are also characterized by single-crystal X-ray diffraction.

Advances in Reversal Strategies of Opioid-induced Respiratory Toxicity

Opioids may produce life-threatening respiratory depression and death from their actions at the opioid receptors within the brainstem respiratory neuronal network. Since there is an increasing number of conditions where the administration of the opioid receptor antagonist naloxone is inadequate or undesired, there is an increased interest in the development of novel reversal and prevention strategies aimed at providing efficacy close to that of the opioid receptor antagonist naloxone but with fewer of its drawbacks such as its short duration of action and lesser ability to reverse high-affinity opioids, such as carfentanil, or drug combinations. To give an overview of this highly relevant topic, the authors systematically discuss predominantly experimental pharmacotherapies, published in the last 5 yr, aimed at reversal of opioid-induced respiratory depression as alternatives to naloxone. The respiratory stimulants are discussed based on their characteristics and mechanism of action: nonopioid controlled substances (e.g., amphetamine, cannabinoids, ketamine), hormones (thyrotropin releasing hormone, oxytocin), nicotinic acetylcholine receptor agonists, ampakines, serotonin receptor agonists, antioxidants, miscellaneous peptides, potassium channel blockers acting at the carotid bodies (doxapram, ENA001), sequestration techniques (scrubber molecules, immunopharmacotherapy), and opioids (partial agonists/antagonists). The authors argue that none of these often still experimental therapies are sufficiently tested with respect to efficacy and safety, and many of the agents presented have a lesser efficacy at deeper levels of respiratory depression, i.e., inability to overcome apnea, or have ample side effects. The authors suggest development of reversal strategies that combine respiratory stimulants with naloxone. Furthermore, they encourage collaborations between research groups to expedite development of viable reversal strategies of potent synthetic opioid-induced respiratory depression.

Antidepressants abuse in subjects with opioid use disorders: A 10-year study in the French OPPIDUM program

Accumulating evidence shows that some antidepressants are abused for their psychostimulant effects, but the extent of antidepressants abuse is unknown in subjects with opioid use disorders (OUD). The objective of this work is to assess the prevalence of antidepressant abuse and its correlates in subjects with OUD. Subjects ≥18 year-old in an opiate maintenance treatment (OMT) program who reported using an antidepressant were selected from the OPPIDUM program from 2011 to 2020. The outcome was antidepressant abuse. Antidepressant abusers were identified as subjects reporting at least one of the following behaviors: "drug abuse," "concomitant use of alcohol," "illegal obtaining," and "dose higher than recommended in the Summary of Product Characteristics." Among the 83 040 observations of subjects ≥18 year-old in an OMT program included in the OPPIDUM program from 2011 to 2020, 2708 (3.3%) subjects reported using an antidepressant in monotherapy. Among them, there were 385 (14.2%) abusers. The proportion of abusers was the highest for amitriptyline (n = 31, 25.0%). In multivariate analysis, antidepressant abuse was positively associated with amitriptyline (OR 2.07, 95% CI [1.16, 3.73]; p = 0.015), unemployment (OR 1.52, 95% CI [1.16, 2.01]; p = 0.003), the use of intravenous route of administration (OR 1.77, 95% CI [1.12, 2.80]; p = 0.014), and the use of benzodiazepines (OR 1.53, 95% CI [1.21, 1.94]; p < 0.001). Clinicians should be aware of the risk of antidepressant abuse when prescribing in subjects with OUD, accounting for their heterogeneous pharmacological properties that may account for their abuse potential.

Tianeptine, but not fluoxetine, decreases avoidant behavior in a mouse model of early developmental exposure to fluoxetine

Depression and anxiety, two of the most common mental health disorders, share common symptoms and treatments. Most pharmacological agents available to treat these disorders target monoamine systems. Currently, finding the most effective treatment for an individual is a process of trial and error. To better understand how disease etiology may predict treatment response, we studied mice exposed developmentally to the selective serotonin reuptake inhibitor (SSRI) fluoxetine (FLX). These mice show the murine equivalent of anxiety- and depression-like symptoms in adulthood and here we report that these mice are also behaviorally resistant to the antidepressant-like effects of adult SSRI administration. We investigated whether tianeptine (TIA), which exerts its therapeutic effects through agonism of the mu-opioid receptor instead of targeting monoaminergic systems, would be more effective in this model. We found that C57BL/6J pups exposed to FLX from postnatal day 2 to 11 (PNFLX, the mouse equivalent in terms of brain development to the human third trimester) showed increased avoidant behaviors as adults that failed to improve, or were even exacerbated, by chronic SSRI treatment. By contrast, avoidant behaviors in these same mice were drastically improved following chronic treatment with TIA. Overall, this demonstrates that TIA may be a promising alternative treatment for patients that fail to respond to typical antidepressants, especially in patients whose serotonergic system has been altered by in utero exposure to SSRIs.

Tianeptine induces expression of dual specificity phosphatases and evokes rebound emergence of cortical slow wave electrophysiological activity

BACKGROUND

The precise mechanism governing the antidepressant effects of tianeptine is unknown. Modulation of brain glutamatergic neurotransmission has been however implicated, suggesting potential shared features with rapid-acting antidepressants targeting N-methyl-D-aspartate receptors (NMDAR). Our recent studies suggest that a single subanesthetic dose of NMDAR antagonists ketamine or nitrous oxide (N₂O) gradually evoke 1-4 Hz electrophysiological activity (delta-rhythm) of cerebral cortex that is accompanied by molecular signaling associated with synaptic plasticity (e.g. activation of tropomyosin receptor kinase B (TrkB) and inhibition of glycogen synthase kinase 3β (GSK3β)).

METHODS

We have here investigated the time-dependent effects of tianeptine (30 mg/kg, i.p.) on electrocorticogram, focusing on potential biphasic regulation of the delta-rhythm. Selected molecular markers associated with ketamine's antidepressant effects were analyzed in the medial prefrontal cortex after the treatment using quantitative polymerase chain reaction and western blotting.

RESULTS

An acute tianeptine treatment induced changes of electrocorticogram typical for active wakefulness that lasted for 2-2.5 h, which was followed by high amplitude delta-activity rebound. The levels of Arc and Homer1a, but not c-Fos, BdnfIV and Zif268, were increased by tianeptine. Phosphorylation of mitogen-activated protein kinase (MAPK), TrkB and GSK3β remained unaltered at 2-hours and at 3-hours post-treatment. Notably, tianeptine also increased the level of mRNA of several dual specificity phosphatases (Duspss) - negative regulators of MAPK.

CONCLUSION

Tianeptine produces acute changes of electrocorticogram resembling rapid-acting antidepressants ketamine and N₂O. Concomitant regulation of Dusps may hamper the effects of tianeptine on MAPK pathway and influence the magnitude of homeostatic emergence of delta-activity and TrkB-GSK3β signaling.

Tianeptine modulates synaptic vesicle dynamics and favors synaptic mitochondria processes in socially isolated rats

Deregulation of synaptic function and neurotransmission has been linked with the development of major depression disorder (MDD). Tianeptine (Tian) has been used as antidepressant with anxiolytic properties and recently as a nootropic to improve cognitive performance, but its mechanism of action is unknown. We conducted a proteomic study on the hippocampal synaptosomal fractions of adult male Wistar rats exposed to chronic social isolation (CSIS, 6 weeks), an animal model of depression and after chronic Tian treatment in controls (nootropic effect) and CSIS-exposed rats (lasting 3 weeks of 6-week CSIS) (therapeutic effect). Increased expression of Syn1 and Camk2-related neurotransmission, vesicle transport and energy processes in Tian-treated controls were found. CSIS led to upregulation of proteins associated with actin cytoskeleton, signaling transduction and glucose metabolism. In CSIS rats, Tian up-regulated proteins involved in mitochondrial energy production, mitochondrial transport and dynamics, antioxidative defense and glutamate clearance, while attenuating the CSIS-increased glycolytic pathway and cytoskeleton organization proteins expression and decreased the expression of proteins involved in V-ATPase and vesicle endocytosis. Our overall findings revealed that synaptic vesicle dynamics, specifically exocytosis, and mitochondria-related energy processes might be key biological pathways modulated by the effective nootropic and antidepressant treatment with Tian and be a potential target for therapeutic efficacy of the stress-related mood disorders.

Experimental considerations for the assessment of in vivo and in vitro opioid pharmacology

Morphine and other mu-opioid receptor (MOR) agonists remain the mainstay treatment of acute and prolonged pain states worldwide. The major limiting factor for continued use of these current opioids is the high incidence of side effects that result in loss of life and loss of quality of life. The development of novel opioids bereft, or much less potent, at inducing these side effects remains an intensive area of research, with multiple pharmacological strategies being explored. However, as with many G protein-coupled receptors (GPCRs), translation of promising candidates from in vitro characterisation to successful clinical candidates still represents a major challenge and attrition point. This review summarises the preclinical animal models used to evaluate the key opioid-induced behaviours of antinociception, respiratory depression, constipation and opioid-induced hyperalgesia and tolerance. We highlight the influence of distinct variables in the experimental protocols, as well as the potential implications for differences in receptor reserve in each system. Finally, we discuss how methods to assess opioid action in vivo and in vitro relate to each other in the context of bridging the translational gap in opioid drug discovery.

Site selective C-H functionalization of Mitragyna alkaloids reveals a molecular switch for tuning opioid receptor signaling efficacy

Mitragynine (MG) is the most abundant alkaloid component of the psychoactive plant material "kratom", which according to numerous anecdotal reports shows efficacy in self-medication for pain syndromes, depression, anxiety, and substance use disorders. We have developed a synthetic method for selective functionalization of the unexplored C11 position of the MG scaffold (C6 position in indole numbering) via the use of an indole-ethylene glycol adduct and subsequent iridium-catalyzed borylation. Through this work we discover that C11 represents a key locant for fine-tuning opioid receptor signaling efficacy. 7-Hydroxymitragynine (7OH), the parent compound with low efficacy on par with buprenorphine, is transformed to an even lower efficacy agonist by introducing a fluorine substituent in this position (11-F-7OH), as demonstrated in vitro at both mouse and human mu opioid receptors (mMOR/hMOR) and in vivo in mouse analgesia tests. Low efficacy opioid agonists are of high interest as candidates for generating safer opioid medications with mitigated adverse effects.

Novel Targets to Treat Depression: Opioid-Based Therapeutics

After participating in this activity, learners should be better able to:• Identify the effects of dysregulated opioid signalling in depression• Evaluate the use of opioid compounds and ketamine in patients with depression ABSTRACT: Major depressive disorder (MDD) remains one of the leading causes of disability and functional impairment worldwide. Current antidepressant therapeutics require weeks to months of treatment prior to the onset of clinical efficacy on depressed mood but remain ineffective in treating suicidal ideation and cognitive impairment. Moreover, 30%-40% of individuals fail to respond to currently available antidepressant medications. MDD is a heterogeneous disorder with an unknown etiology; novel strategies must be developed to treat MDD more effectively. Emerging evidence suggests that targeting one or more of the four opioid receptors-mu (MOR), kappa (KOR), delta (DOR), and the nociceptin/orphanin FQ receptor (NOP)-may yield effective therapeutics for stress-related psychiatric disorders. Furthermore, the effects of the rapidly acting antidepressant ketamine may involve opioid receptors. This review highlights dysregulated opioid signaling in depression, evaluates clinical trials with opioid compounds, and considers the role of opioid mechanisms in rapidly acting antidepressants.

Effect of neuropsychiatric medications on mitochondrial function: For better or for worse

Individuals with mitochondrial disease often present with psychopathological comorbidity, and mitochondrial dysfunction has been proposed as the underlying pathobiology in various psychiatric disorders. Several studies have suggested that medications used to treat neuropsychiatric disorders could directly influence mitochondrial function. This review provides a comprehensive overview of the effect of these medications on mitochondrial function. We collected preclinical information on six major groups of antidepressants and other neuropsychiatric medications and found that the majority of these medications either positively influenced mitochondrial function or showed mixed effects. Only amitriptyline, escitalopram, and haloperidol were identified as having exclusively adverse effects on mitochondrial function. In the absence of formal clinical trials, and until such trials are completed, the data from preclinical studies reported and discussed here could inform medication prescribing practices for individuals with psychopathology and impaired mitochondrial function in the underlying pathology.

Activation of liver X receptors prevents emotional and cognitive dysfunction by suppressing microglial M1-polarization and restoring synaptic plasticity in the hippocampus of mice

Depression is a long-lasting and persistent mood disorder in which the regulatory mechanisms of neuroinflammation are thought to play a contributing role to the physiopathology of the condition. Previous studies have shown that liver X receptors (LXRs) can regulate the activation of microglia and neuroinflammation. However, the role of LXRs in depression remains to be fully understood. In this study, we hypothesized that stress impairs the function of LXRs and that the LXRs agonist GW3965 plays a potential anti-depressive role by inhibiting neuroinflammation. The anti-depressive effects of GW3965 were evaluated in both chronic unpredictable mild stress (CUMS) and lipopolysaccharide (LPS) models. The LXRs antagonist GSK2033 was also employed to block LXRs. Behavioural tests were performed to measure depression-like phenotypes and learning abilities. Electrophysiological recordings and Golgi staining were used to measure the plasticity of the dentate gyrus synapse. The expression of synapse and neuroinflammation related proteins were evaluated by Western blotting and immunofluorescence. The activation of LXRs by GW3965 prevented emotional and cognitive deficits induced by either CUMS or LPS. GW3965 prevented the decreased level of LXR-β induced by CUMS. The activation of LXRs significantly improved the impairment of synaptic plasticity, prevented the up-regulation of inflammatory factors and inhibited NF-κB phosphorylation and microglial M1-polarization in both models. The antidepressive-like effects of GW3965 were blocked by GSK2033 in the CUMS and LPS models. Our data suggest that inhibition of the LXRs signalling pathway may be a key driver in the pathogenesis of neuroinflammation during depression and that LXRs agonists have a high potential in the treatment of depression.

When an obscurity becomes trend: social-media descriptions of tianeptine use and associated atypical drug use

Background: Originally believed to be an atypical antidepressant acting at serotonin transporters, tianeptine is now known to also be an atypical agonist at mu-opioid receptors. Its nonmedical use may be increasing amidst the broader context of novel drug and supplement use.Objectives: To analyze social-media text from current, former, and prospective tianeptine users for better understanding of their conceptualizations of tianeptine, motives for and patterns of use, and reported benefits and harms.Methods: Reddit posts were obtained and thematically coded; additional quantitative analyses were conducted.Results: A total of 210 posts mentioning tianeptine were made between 2012 and 2020. Eighteen thematic categories were identified, 10 of which were consistent with expected themes. Two independent raters coded all text, generating 1,382 unique codes, of which 1,090 were concordant (78.9% interrater agreement). Tianeptine use was frequently associated with use of other drugs, particularly kratom, phenibut, and racetams. People conceptualized and variously used tianeptine as an opioid, antidepressant, and "nootropic" (cognitive enhancer). Between 2014 and 2020, mentions of positive effects decreased, while mentions of adverse effects and withdrawal increased. Motivations for use included substitution or withdrawal mitigation for other drugs (especially opioids) and for kratom itself; self-treatment for psychiatric symptoms; and improvement of quality of life, mood, or performance. Descriptions of tolerance, withdrawal, and addiction were evident. Intravenous use was rare and strongly discouraged, with detrimental effects described.Conclusion: Tianeptine is recognized as an opioid (though not only an opioid) in online communities. Posts describe benefits, acute risks, and patterns of co-use that warrant greater clinical attention.

Neuroendocrine Assessment of Dopaminergic Function during Antidepressant Treatment in Major Depressed Patients

The effects of antidepressants on dopamine (DA) receptor sensitivity in the mesolimbic-hypothalamic system have yielded contradictory results. The postsynaptic DA receptor function was evaluated by the cortisol response to apomorphine (APO; 0.75 mg SC) in 16 drug-free DSM-5 major depressed inpatients and 18 healthy hospitalized control (HC) subjects. Cortisol response to the dexamethasone suppression test (DST) was also measured. After two and four weeks of antidepressant treatment (ADT), the DST and APO test were repeated in all patients. Cortisol response to APO (∆COR) was not influenced by the hypothalamic-pituitary-adrenal (HPA) axis activity, as assessed by the DST. Pre-treatment ∆COR values did not differ significantly between patients and HCs. During ADT, ∆COR values were lower than in HCs at week 2 and 4. After four weeks of treatment, among the eight patients who had blunted ∆COR values, seven were subsequent remitters, while among the eight patients who had normal ∆COR values, seven were non-remitters. Considering the limitations of our study, the results suggest that following chronic ADT, the desensitization of postsynaptic DA receptors connected with the regulation of the HPA axis at the hypothalamic level is associated with clinical remission. These results could reflect increased DA levels in the mesolimbic pathway.

Association of Sleep Architecture and Physiology with Depressive Disorder and Antidepressants Treatment

Sleep problems are frequently associated with the principal diagnostic criteria for many mental disorders. Alterations in the sleep of depressive patients are of high clinical significance because continuous sleep problems raise the chance of relapse, recurrence, or suicide, as well as the need for augmenting medications. Most antidepressants have been proven to influence the sleep architecture. While some classes of antidepressants improve sleep, others may cause sleep impairment. The successful treatment of depressive disorder also requires an understanding of the effects of antidepressants on sleep. This article briefly reviews the physiology of sleep and the typical alterations in the sleep architecture in depressive patients and updates the different effects of the majority of antidepressants including novel drugs in clinical practice on sleep. The summary of the updated scientific findings of the relationship between depression and sleep disturbances could be clinically beneficial in choosing the best medication for depressive patients with concurrent sleep disorders.

Early Detection of Prescription Drug Abuse Using Doctor Shopping Monitoring From Claims Databases: Illustration From the Experience of the French Addictovigilance Network

Opioid analgesics and maintenance treatments, benzodiazepines and z-drugs, and other sedatives and stimulants are increasingly being abused to induce psychoactive effects or alter the effects of other drugs, eventually leading to dependence. Awareness of prescription drug abuse has been increasing in the last two decades, and organizations such as the International Narcotics Control Board has predicted that, worldwide, prescription drug abuse may exceed the use of illicit drugs. Assessment of prescription drug abuse tackles an issue that is hidden by nature, which therefore requires a specific monitoring. The current best practice is to use multiple detection systems to assess prescription drug abuse by various populations in a timely, sensitive, and specific manner. In the early 2000's, we designed a method to detect and quantify doctor shopping for prescription drugs from the French National Health Data System, which is one of the world's largest claims database, and a first-class data source for pharmacoepidemiological studies. Doctor shopping is a well-known behavior that involves overlapping prescriptions from multiple prescribers for the same drug, to obtain higher doses than those prescribed by each prescriber on an individual basis. In addition, doctor shopping may play an important role in supplying the black market. The paper aims to review how doctor shopping monitoring can improve the early detection of prescription drug abuse within a multidimensional monitoring. The paper provides an in-depth overview of two decades of development and validation of the method as a complementary component of the multidimensional monitoring conducted by the French Addictovigilance Network. The process accounted for the relevant determinants of prescription drug abuse, such as pharmacological data (e.g., formulations and doses), chronological and geographical data (e.g., impact of measures and comparison between regions), and epidemiological and outcome data (e.g., profiles of patients and trajectories of care) for several pharmacological classes (e.g., opioids, benzodiazepines, antidepressants, and methylphenidate).

Corticotropin releasing hormone receptor CRHR1 gene is associated with tianeptine antidepressant response in a large sample of outpatients from real-life settings

Polymorphisms of genes involved in the hypothalamic-pituitary-adrenocortical (HPA) axis have been associated with response to several antidepressant treatments in patients suffering of depression. These pharmacogenetics findings have been reported from independent cohorts of patients mostly treated with selective serotonin reuptake inhibitors, tricyclic antidepressant, and mirtazapine. Tianeptine, an atypical antidepressant, recently identified as a mu opioid receptor agonist, which prevents and reverses the stress induced by glucocorticoids, has been investigated in this present pharmacogenetics study. More than 3200 Caucasian outpatients with a major depressive episode (MDE) from real-life settings were herein analyzed for clinical response to tianeptine, a treatment initiated from 79.5% of the subjects, during 6-8 weeks follow-up, assessing polymorphisms targeting four genes involved in the HPA axis (NR3C1, FKPB5, CRHR1, and AVPR1B). We found a significant association (p < 0.001) between CRHR1 gene variants rs878886 and rs16940665, or haplotype rs878886*C-rs16940665*T, and tianeptine antidepressant response and remission according to the hospital anxiety and depression scale. Analyses, including a structural equation model with simple mediation, suggest a moderate effect of sociodemographic characteristics and depressive disorder features on treatment response in individuals carrying the antidepressant responder allele rs8788861 (allele C). These findings suggest direct pharmacological consequences of CRHR1 polymorphisms in the antidepressant tianeptine response and remission, in MDE patients. This study replicates the association of the CRHR1 gene, involved in the HPA axis, with (1) a specificity attributed to treatment response, (2) a lower risk of chance finding, and in (3) an ecological situation.

Polymorphisms of stress pathway genes and emergence of suicidal ideation at antidepressant treatment onset

The prescription of antidepressant drugs is one of the most frequently used strategies to prevent suicide and suicidal behavior. However, some patients develop suicidal ideation at antidepressant treatment onset, a phenomenon known as treatment-emergent suicidal ideation (TESI). Few studies have explored TESI pharmacogenomics. As the Hypothalamic-Pituitary-Adrenal (HPA) axis might be implicated in suicidal behavior, we assessed the relationship between TESI and single nucleotide polymorphisms (SNPs) in the HPA axis-implicated NR3C1 (n = 7 SNPs), FKBP5 (n = 5 SNPs), AVPR1B (n = 1 SNPs), CRHR1 (n = 1 SNPs), and SKA2 (n = 1 SNPs) genes, in a sample of 3566 adult outpatients with depression for whom an antidepressant treatment was introduced. General practitioners and psychiatrists throughout France followed participants for 6 weeks after the initial prescription of tianeptine, an antidepressant molecule showing mu agonism. Suicidal ideation was assessed with item 10 of the Montgomery-Åsberg Depression Rating Scale (item dedicated to suicidal ideation) at baseline, and at week 2, 4, and 6 of treatment. Within the informative sample, 112 patients reported TESI and 384 did not. TESI was significantly associated with the TT genotype of the SNP rs6902321 in FKBP5 (OR = 1.76, 95% CI = [1.07; 2.90]; p-value = 0.03) and the GG/AG genotype of the SNP rs7208505 in SKA2 (OR = 1.85, 95% CI = [1.03;3.33]; p-value = 0.04). These associations were not significant after multiple test correction. Nevertheless, our results suggest a possible involvement of HPA axis elements in treatment-emergent suicidal ideation (TESI).

Endogenous Opioids at the Intersection of Opioid Addiction, Pain, and Depression: The Search for a Precision Medicine Approach

Opioid addiction and overdose are at record levels in the United States. This is driven, in part, by their widespread prescription for the treatment of pain, which also increased opportunity for diversion by sensation-seeking users. Despite considerable research on the neurobiology of addiction, treatment options for opioid abuse remain limited. Mood disorders, particularly depression, are often comorbid with both pain disorders and opioid abuse. The endogenous opioid system, a complex neuromodulatory system, sits at the neurobiological convergence point of these three comorbid disease states. We review evidence for dysregulation of the endogenous opioid system as a mechanism for the development of opioid addiction and/or mood disorder. Specifically, individual differences in opioid system function may underlie differences in vulnerability to opioid addiction and mood disorders. We also review novel research, which promises to provide more detailed understanding of individual differences in endogenous opioid neurobiology and its contribution to opioid addiction susceptibility.

Characteristics of tianeptine effects reported to a poison control center: a growing threat to public health

BACKGROUND

Tianeptine is an antidepressant structurally similar to tricyclic antidepressants which is approved abroad but is currently a drug of abuse in the United States since at least 2000. In 2019, our poison center experienced an increase in calls relating to this xenobiotic. The goal of this report is to describe the characteristics of acute tianeptine intoxication and withdrawal.

METHODS

All calls to a statewide poison center regarding tianeptine were reviewed from January 1, 2015 to March 15, 2020. Cases were identified using the American Association of Poison Control Centers' substance code for "other types of tricyclic antidepressants." Cases were excluded if they did not involve tianeptine. Date of call, patient demographics, symptoms, cardiac intervals if available, and disposition were recorded.

RESULTS

Eighty-four cases of atypical tricyclic antidepressants were identified in the study period. Forty-eight cases involving tianeptine met inclusion criteria and were reviewed. Of these, 37 (77%) occurred from May 2019 to March 2020. Twenty-seven (56%) required medical admission including 17 cases (35%) that were managed in an intensive care unit. Seventeen of the 48 cases resulted from acute tianeptine intoxication. Lethargy was the most common presentation, but some patients also presented with agitation. Thirty-one (65%) of the cases resulted from tianeptine withdrawal, which usually exhibited agitation, anxiety, gastrointestinal distress. Naloxone was used in 4 cases (24%) of the acute intoxication cohort and benzodiazepines were frequently used both in acutely intoxicated patients and in patients experiencing tianeptine withdrawal. No patients in either cohort had cardiac conduction disturbances.

CONCLUSION

Our center observed a dramatic rise in tianeptine toxicity, particularly in patients experiencing withdrawal symptoms, beginning in May 2019. More than half of the cases required medical admission including a third who were treated in the intensive care unit. Health care practitioners should be increasingly aware of this xenobiotic as usage may be on the rise.