Pharmacotherapy for Treatment-Resistant Depression: Antidepressants and Atypical Antipsychotics

Chronic, combinatorial targeting of NMDARs and 5-HT4Rs exerts extended behavioral effects against stress-induced perseverative behavior and hyponeophagia

Serotonin (5-HT) receptors and N-methyl-D-aspartate receptors (NMDARs) have both been implicated in stress-induced psychiatric disorders. However, there is a paucity of studies evaluating the effectiveness of novel combinatorial pharmacological treatments to treat stress-related disorders. Here, we evaluated whether administration of combinatorial (R,S)-ketamine, an NMDAR antagonist and Food and Drug Administration (FDA)-approved anesthetic, and prucalopride, a 5-HT type IV receptor (5-HT4R) agonist and FDA-approved drug for chronic idiopathic constipation (CIC), would have additional effects when administered after stress. A single injection of saline (Sal), (R,S)-ketamine (K), prucalopride (P), or a combined dose of (R,S)-ketamine and prucalopride (K + P) was administered for 1x, 2x, or 7x per week for 2 weeks after either contextual fear conditioning (CFC), learned helplessness (LH), stress enhanced fear learning (SEFL), or chronic corticosterone (CORT) stress in both sexes. Drug efficacy was assayed using assays to measure fear, behavioral despair, perseverative, and/or hyponeophagia. Combinatorial drug administration was also tested using intranasal delivery. We found that combinatorial K + P exerted additional effects, compared to either drug alone, in reducing a variety of stress-induced behaviors in both sexes. Moreover, intranasal dosing was also effective. Our results indicate that chronic administration of K + P has extended benefits for combating stress-induced pathophysiology. Our findings provide strong evidence that future clinical studies using this chronic treatment strategy may prove advantageous in decreasing a broad range of stress-induced psychiatric disorders.

Reversal potentials of Tween 20 in ABC transporter-mediated multidrug-resistant cancer and treatment-resistant depression through interacting with both drug-binding and ATP-binding areas on MDR proteins

Drug efflux transporters, especially those belonging to the ATP-binding cassette (ABC) transporter superfamily, play a crucial role in various drug resistance issues, including multidrug resistance (MDR) in cancer and treatment-resistant depression (TRD) in individuals with major depressive disorder. Key transporters in this context include P-glycoprotein (P-gp), multidrug resistance protein 1 (MRP1), and breast cancer resistance protein (BCRP). This study aimed to investigate the modulatory effects of polyoxyethylene (20) sorbitan monolaurate (Tween 20) on these efflux transporters in vitro and to evaluate its potential for overcoming drug resistance in two models: an in vitro cancer MDR model and an in vivo TRD model. The findings indicated that 0.001% Tween 20 significantly inhibited the efflux actions of all three transporters. Additionally, 0.005% Tween 20 effectively reversed resistance to paclitaxel, vincristine, doxorubicin, and mitoxantrone in various cancer MDR cell lines. In the in vivo depression-like behaviour model, 0.01% Tween 20 markedly enhanced the antidepressant and anxiolytic effects of fluoxetine. Given its strong inhibitory effects on P-gp, MRP1, and BCRP, along with its capacity to reverse drug resistance both in vitro and in vivo, Tween 20 is a compelling candidate for tackling transporter-mediated drug resistance.

Effect of Deregulation of the Brazilian National Controlled Products Management System on Antidepressants' Sales Data Deregulation of a Brazilian Drug Electronic System

PURPOSE

To assess the effect of deregulating the national sales reporting system on Brazilian pharmacoepidemiologic data on antidepressants.

METHODS

This was a time series analysis to assess the trends in antidepressant sales in Brazilian drugstores from January 2014 to December 2022 using the Brazilian National Controlled Products Management System (SNGPC) and to predict sales records for 2022 after the deregulation of the mandatory record in December 2021. Antidepressant sales were converted to defined daily doses per 1000 inhabitants per day (DID). The seasonal autoregressive integrated moving average (SARIMA) was used to predict sales records for 2022. All analyses were conducted in Stata v.14.2.

RESULTS

Sales of patients taking antidepressants increased significantly from 2014 (mean: 14.7 DID/month) to 2020 (mean: 33.5 DID/month; β = 0.231; p < 0.001). After the start of the COVID-19 pandemic, the increasing trend continued, but the change was not significant (β = 0.330; p = 0.130). After the deregulation, a sharp decrease was observed (β = -1.032; p < 0.001). The monthly antidepressant sales forecasted for 2022 were 36.5 DID, while the observed value was 2.5 DID.

CONCLUSION

Deregulation of SNGPC registration significantly decreased the number of antidepressant sales records. This measure affected the availability of pharmacoepidemiological data and research in Brazil.

Bibliometric analysis of research hotspots and trends on the relationship between the gut microbiota and depression from 2020 to 2024

INTRODUCTION

In recent years, an increasing body of research has illustrated a strong correlation between gut microbiota and depression. However, there has yet to be a comprehensive discussion or summary of the latest advancements and trends in this field.

METHODS

We retrieved research articles focused on gut microbiota and depression through the WOS database from 2020 to 2024, using visual text analysis tools such as CiteSpace and VOSviewer.

RESULTS

The literature on the relationship between gut microbiota and depression surged from 396 papers in 2020 to 711 by 2024. During this period, the journal with the highest publication rate was Nutrients. China led the countries in contributions, while University College Cork topped the institutions. Kenji Hashimoto emerged as the most prolific author. The most cited paper was authored by Cryan JF et al., published in 2019 in Physiol Rev. The keywords "gut microbiota," "depression," and "anxiety" appeared most frequently, while recent years saw explosive increases in terms such as "growth performance," "receptors," "depression-like phenotypes," "stress response," "gastrointestinal symptoms," "reliability," and "neurogenesis."

DISCUSSION

Our article displayed the overview of the relationship between the gut microbiome and depression from 2020 to 2024 using bibliometric methods, providing perspectives and research hotspots for studies exploring the correlation between the gut microbiome and depression.

Bidirectional relationship between diabetes mellitus and depression: Mechanisms and epidemiology

Diabetes mellitus and depression exhibit a complex bidirectional relationship that profoundly impacts patient health and quality of life. This review explores the physiological mechanisms, including inflammation, oxidative stress, and neuroendocrine dysregulation, that link these conditions. Psychosocial factors such as social support and lifestyle choices also contribute significantly. Epidemiological insights reveal a higher prevalence of depression among diabetics and an increased risk of diabetes in depressed individuals, influenced by demographic variables. Integrated management strategies combining mental health assessments and personalized treatments are essential. Future research should focus on longitudinal and multi-omics studies to deepen understanding and improve therapeutic outcomes.

Antipsychotic agents in anxiety disorders: An umbrella review

BACKGROUND

Although not approved for the treatment of anxiety disorders (except trifluoperazine) there is ongoing off-label, unapproved use of first-generation antipsychotics (FGAs) and second-generation antipsychotics (SGAs) for anxiety disorders. There have been systematic reviews and meta-analyses on the use of antipsychotics in anxiety disorders, most of which focused on SGAs.

OBJECTIVE

The specific aims of this umbrella review are to: (1) Evaluate the evidence of efficacy of FGAs and SGAs in anxiety disorders as an adjunctive treatment to traditional antidepressant treatments and other nonantipsychotic medications; (2) Compare monotherapy with antipsychotics to first-line treatments for anxiety disorders in terms of effectiveness, risks, and side effects. The review protocol is registered on PROSPERO (CRD42021237436).

METHODS

An initial search was undertaken to identify systematic reviews and meta-analyses from inception until 2020, with an updated search completed August 2021 and January 2023. The searches were conducted in PubMed, MEDLINE (Ovid), EMBASE (Ovid), APA PsycInfo (Ovid), CINAHL Complete (EBSCOhost), and the Cochrane Library through hand searches of references of included articles. Review quality was measured using the AMSTAR-2 (A MeaSurement Tool to Assess Systematic Reviews) scale.

RESULTS

The original and updated searches yielded 1796 and 3744 articles respectively, of which 45 were eligible. After final review, 25 systematic reviews and meta-analyses were included in the analysis. Most of the systematic reviews and meta-analyses were deemed low-quality through AMSTAR-2 with only one review being deemed high-quality. In evaluating the monotherapies with antipsychotics compared with first-line treatments for anxiety disorder there was insufficient evidence due to flawed study designs (such as problems with randomization) and small sample sizes within studies. There was limited evidence suggesting efficacy of antipsychotic agents in anxiety disorders other than quetiapine in generalized anxiety disorder (GAD).

CONCLUSIONS

This umbrella review indicates a lack of high-quality studies of antipsychotics in anxiety disorders outside of the use of quetiapine in GAD. Although potentially effective for anxiety disorders, FGAs and SGAs may have risks and side effects that outweigh their efficacy, although there were limited data. Further long-term and larger-scale studies of antipsychotics in anxiety disorders are needed.

Plasma Brain-Derived Neurotrophic Factor Levels in First-Episode and Recurrent Major Depression and before and after Bright Light Therapy in Treatment-Resistant Depression

Brain-derived neurotrophic factor (BDNF) is implicated in the etiology and treatment response in major depressive disorder (MDD). However, peripheral BDNF concentrations have not been compared across different MDD stages. Bright light therapy (BLT) offers some potential in treatment-resistant depression (TRD), but its effects on BDNF levels are unknown. This study included a cross-sectional analysis of plasma BDNF concentration in females with TRD, unmedicated MDD patients, and healthy controls (HC), and measurements of longitudinal BLT effects on plasma BDNF levels in TRD patients. The present study included 55 drug-naïve, first-episode patients, 25 drug-free recurrent-episode MDD patients, 71 HC participants, and 54 TRD patients. Patients were rated by Hamilton Depression Rating Scale (HAMD)-17 and the Montgomery-Åsberg Depression Rating Scale (MADRS). Patients with TRD received BLT during 4 weeks. The total HAMD-17 and MADRS scores decreased following BLT. All patient groups had lower plasma BDNF than HC, but BDNF levels did not differ between first- and recurrent-episode BDNF patients and TRD patients before or after BLT. However, responders and remitters to BLT had higher post-treatment plasma BDNF concentrations than patients who did not achieve response or remission. The changes in plasma BDNF levels may be candidates for biomarkers of treatment response to BLT in TRD patients.