Double-blind, randomized, placebo-controlled pilot study of the phosphodiesterase-3 inhibitor cilostazol as an adjunctive to antidepressants in patients with major depressive disorder

Can Adipokine FAM19A5 Be a Biomarker of Metabolic Disorders?

Aim

One of the most critical functions of adipose tissue is the production of adipokines, ie, numerous active substances that regulate metabolism. One is the newly discovered FAM19A5, whose older name is TAFA-5.

Purpose

The study aimed to review the literature on the FAM19A5 protein.

Methods

The review was conducted in December 2023 using the PubMed (Medline) search engine. Sixty-four papers were included in the review.

Results

This protein exhibits the characteristics of an adipokine with positive features for maintaining homeostasis. The results showed that FAM19A5 was highly expressed in adipose tissue, with mild to moderate expression in the brain and ovary. FAM19A5 may also inhibit vascular smooth muscle cell proliferation and migration through the perivascular adipose tissue paracrine pathway. Serum levels of FAM19A5 were decreased in obese children compared with healthy controls. There are negative correlations between FAM19A5, body mass index, and fasting insulin. Serum FAM19A5 level is correlated with type 2 diabetes, waist circumference, waist-to-hip ratio, glutamic pyruvic transferase, fasting plasma glucose, HbA1c, and mean shoulder pulse wave velocity. FAM19A5 expression was reduced in mice with obesity. However, the data available needs to be clarified or contradictory.

Conclusion

Considering today's knowledge about FAM19A5, we cannot consider this protein as a biomarker of the metabolic syndrome. According to current knowledge, FAM19A5 cannot be considered a marker of metabolic disorders because the results of studies conducted in this area are unclear.

Identifying plasma metabolic characteristics of major depressive disorder, bipolar disorder, and schizophrenia in adolescents

Major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SCZ) are classified as major mental disorders and together account for the second-highest global disease burden, and half of these patients experience symptom onset in adolescence. Several studies have reported both similar and unique features regarding the risk factors and clinical symptoms of these three disorders. However, it is still unclear whether these disorders have similar or unique metabolic characteristics in adolescents. We conducted a metabolomics analysis of plasma samples from adolescent healthy controls (HCs) and patients with MDD, BD, and SCZ. We identified differentially expressed metabolites between patients and HCs. Based on the differentially expressed metabolites, correlation analysis, metabolic pathway analysis, and potential diagnostic biomarker identification were conducted for disorders and HCs. Our results showed significant changes in plasma metabolism between patients with these mental disorders and HCs; the most distinct changes were observed in SCZ patients. Moreover, the metabolic differences in BD patients shared features with those in both MDD and SCZ, although the BD metabolic profile was closer to that of MDD than to SCZ. Additionally, we identified the metabolites responsible for the similar and unique metabolic characteristics in multiple metabolic pathways. The similar significant differences among the three disorders were found in fatty acid, steroid-hormone, purine, nicotinate, glutamate, tryptophan, arginine, and proline metabolism. Interestingly, we found unique characteristics of significantly altered glycolysis, glycerophospholipid, and sphingolipid metabolism in SCZ; lysine, cysteine, and methionine metabolism in MDD and BD; and phenylalanine, tyrosine, and aspartate metabolism in SCZ and BD. Finally, we identified five panels of potential diagnostic biomarkers for MDD-HC, BD-HC, SCZ-HC, MDD-SCZ, and BD-SCZ comparisons. Our findings suggest that metabolic characteristics in plasma vary across psychiatric disorders and that critical metabolites provide new clues regarding molecular mechanisms in these three psychiatric disorders.

Antidepressant mechanisms of ketamine's action: NF-κB in the spotlight

Ketamine recently approved for therapy of treatment-resistant depression shows a complex and not fully understood mechanism of action. Apart from its classical glutamatergic N-methyl-D-aspartate receptor antagonistic action, it is thought that anti-inflammatory properties of the drug are of clinical relevance due to the contribution of activated inflammatory mediators to the pathophysiology of depression and non-responsiveness of a group of patients to current antidepressant therapies. In a search of the mechanism underlying anti-inflammatory effects of ketamine, the nuclear factor kappa B transcription factor (NF-κB) has been proposed as a target for ketamine. The NF-κB forms precisely regulated protein signaling cascades enabling a rapid response to cellular stimuli. In the central nervous systems, NF-κB signaling appears to have pleiotropic but double-edged functions: on the one hand it participates in the regulation of processes that are crucial in the treatment of depression, such as neuroplasticity, neurogenesis or neuronal survival, on the other - in the activation of neuroinflammation and cell death. Ketamine has been found to reduce inflammation mediated by NF-κB, leading to decreased level of pro-inflammatory cytokines and other inflammatory or stress mediators. Therefore, this review presents recent data on the significance of the NF-κB cascade in the mechanism of ketamine's action and its future perspectives in designing new strategies for the treatment of depression.

Effect of cilostazol on preventing paclitaxel-induced neuropathy in patients with breast cancer: A randomized controlled trial

STUDY OBJECTIVE

Paclitaxel-induced peripheral neuropathy is a significant clinical problem can markedly deteriorate patient's quality of life (QoL). Preclinical evidence exists about the preventive capacity of cilostazol against peripheral neuropathy. However, this hypothesis has not yet been clinically investigated. This proof-of-concept study evaluated the effect of cilostazol on the incidence of paclitaxel-induced peripheral neuropathy in patients with non-metastatic breast cancer.

DESIGN

This is a parallel randomized placebo-controlled trial.

SETTING

The Oncology Center at Mansoura University, Egypt.

PATIENTS

Patients with breast cancer scheduled to receive paclitaxel 175 mg/m2 biweekly.

INTERVENTIONS

Patients were randomized to either cilostazol group who received cilostazol tablets 100 mg BID, or to control group who received placebo instead.

MEASUREMENTS

The primary endpoint was the incidence of paclitaxel-induced neuropathy evaluated through common terminology criteria for adverse event (NCI-CTCAE) version 4. Secondary endpoints included assessment of the patient's QoL by the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT-GOG-NTx) subscale. Exploratory outcome measures included changes in serum levels of biomarkers namely nerve growth factor (NGF), and neurofilament light chain (NfL).

MAIN RESULTS

The incidence of grade 2 and 3 peripheral neuropathies were significantly lower in the cilostazol group (40%) compared to the control group (86.7%) (p < 0.001). The incidence of clinically significant worsening in neuropathy-related QoL was higher in control group compared to the cilostazol group (p = 0.001). A higher percent increase from baseline in serum NGF was observed in the cilostazol group (p = 0.043). The circulating levels of NfL deemed comparable between the two arms at the end of the study (p = 0.593).

CONCLUSION

Adjunctive use of cilostazol is as a novel option that might reduce the incidence of paclitaxel-induced peripheral neuropathy and improve the patients' QoL. Future larger clinical trials are warranted to confirm these findings.

Phosphodiesterase inhibitors in psychiatric disorders

RATIONALE

Challenges in drug development for psychiatric disorders have left much room for the introduction of novel treatments with better therapeutic efficacies and indices. As a result, intense research has focused on identifying new targets for developing such pharmacotherapies. One of these targets may be the phosphodiesterase (PDE) class of enzymes, which play important roles in intracellular signaling. Due to their critical roles in cellular pathways, these enzymes affect diverse neurobiological functions from learning and memory formation to neuroinflammation.

OBJECTIVES

In this paper, we reviewed studies on the use of PDE inhibitors (PDEIs) in preclinical models and clinical trials of psychiatric disorders including depression, anxiety, schizophrenia, post-traumatic stress disorder (PTSD), bipolar disorder (BP), sexual dysfunction, and feeding disorders.

RESULTS

PDEIs are able to improve symptoms of psychiatric disorders in preclinical models through activating the cAMP-PKA-CREB and cGMP-PKG pathways, attenuating neuroinflammation and oxidative stress, and stimulating neural plasticity. The most promising therapeutic candidates to emerge from these preclinical studies are PDE2 and PDE4 inhibitors for depression and anxiety and PDE1 and PDE10 inhibitors for schizophrenia. Furthermore, PDE3 and 4 inhibitors have shown promising results in clinical trials in patients with depression and schizophrenia.

CONCLUSIONS

Larger and better designed clinical studies of PDEIs in schizophrenia, depression, and anxiety are warranted to facilitate their translation into the clinic. Regarding the other conditions discussed in this review (most notably PTSD and BP), better characterization of the effects of PDEIs in preclinical models is required before clinical studies.

Cilostazol as adjunctive therapy in treatment of children with autism spectrum disorders: a double-blind and placebo-controlled randomized trial

We aimed to evaluate cilostazol therapeutic effects on aberrant behaviors of autism spectrum disorder (ASD) children and its safety profile in a double-blind, randomized clinical trial. Sixty-six children with confirmed ASD were allocated to receive either daily 50-mg cilostazol (increased to 100 mg/day after 2 weeks) or matched placebo in addition to risperidone. The Aberrant Behavior Checklist-Community Edition (ABC-C) scale and a checklist of probable adverse effects were used to assess the behavioral outcomes and safety profile at weeks 0, 5, and 10 of the study. Sixty-one participants, with comparable baseline characteristics, completed the trial. Unlike other ABC-C subscales, repeated-measures analysis showed significant effect for time × treatment interaction in the hyperactivity subscale ( P = 0.047; partial eta squared = 0.06). We used the median value for the baseline score hyperactivity subscale [median (interquartile range) = 31 (24-37)] to stratify participants to higher hyperactivity and lower hyperactivity subgroups and found that only participants with higher hyperactivity benefit from cilostazol adjunctive therapy ( P = 0.028; partial eta squared = 0.14). Cilostazol could be considered as a safe agent with beneficial effects on hyperactivity in children with ASD and higher levels of hyperactivity.

Phosphodiesterase inhibitor and selective serotonin reuptake inhibitor combination therapy versus monotherapy for the treatment of major depressive disorder: a systematic review and meta-analysis

OBJECTIVE

Selective serotonin reuptakeinhibitors (SSRIs) are the gold standard treatment for major depressive disorder (MDD). However, the use of phosphodiesterase (PDE) inhibitors in the treatment of MDD remains unclear. Our study aims to compare the effect of PDE inhibitor combination therapy to SSRI monotherapy for the treatment of MDD.

METHODS

We performed a comprehensive literature search using PubMed, EMBASE, and Web of Science databases, for studies that assess the impact of PDE inhibitor therapy on MDD patients. The primary outcome of our study was treatment response rate at the end of study time. Pooled odds ratio (OR) and corresponding 95% confidence intervals (CIs) were calculated using the random-effects model. A P-value <0.05 was considered statistically significant.

RESULTS

A total of four randomized control trials (RCTs), including 270 patients with MDD, were included in the analysis. Follow-up periods ranged from 6 to 12 weeks. The PDE inhibitor group was associated with a significantly higher treatment response rate (OR, 4.77; 95% CI, 2.05-11.12; P = 0.0003).

CONCLUSION

Our meta-analysis demonstrated that MDD patients receiving PDE inhibitor combination therapy had a higher treatment response rate than MDD patients receiving SSRI monotherapy. Further large-scale RCTs with long-term follow-ups are necessary to validate our findings.

Microglia Involves in the Immune Inflammatory Response of Poststroke Depression: A Review of Evidence

Poststroke depression (PSD) does not exist before and occurs after the stroke. PSD can appear shortly after the onset of stroke or be observed in the weeks and months after the acute or subacute phase of stroke. The pathogenesis of PSD is unclear, resulting in poor treatment effects. With research advancement, immunoactive cells in the central nervous system, particularly microglia, play a role in the occurrence and development of PSD. Microglia affects the homeostasis of the central nervous system through various factors, leading to the occurrence of depression. The research progress of microglia in PSD has been summarized to review the evidence regarding the pathogenesis and treatment target of PSD in the future.

White Matter Alterations in Depressive Disorder

Depressive disorder is the most prevalent affective disorder today. Depressive disorder has been linked to changes in the white matter. White matter changes in depressive disorder could be a result of impaired cerebral blood flow (CBF) and CBF self-regulation, impaired blood-brain barrier function, inflammatory factors, genes and environmental factors. Additionally, white matter changes in patients with depression are associated with clinical variables such as differential diagnosis, severity, treatment effect, and efficacy assessment. This review discusses the characteristics, possible mechanisms, clinical relevance, and potential treatment of white matter alterations caused by depressive disorders.

Cilostazol as an adjunctive treatment in major depressive disorder: a pilot randomized, double-blind, and placebo-controlled clinical trial

BACKGROUND

Cilostazol, a phosphodiesterase-3 inhibitor, has been reported to improve depressive-like behavior in experimental studies of depression. We investigated the safety and efficacy of cilostazol combination therapy with sertraline in treating patients with major depressive disorder (MDD) in a 6-week, parallel, randomized controlled trial.

METHOD

Among patients referred to the outpatient clinic of a tertiary hospital, those with a diagnosis of MDD with moderate to severe severity (a score of >19 on the Hamilton depression rating scale (HAM-D)) were enrolled. A total of 54 MDD patients aged 18-65 years were randomly assigned to either the cilostazol (100 mg daily) or the placebo group. Both groups received sertraline 100 mg per day similarly. Changes in HAM-D at weeks 2, 4, and 6 were the primary outcome. Participants and outcome assessors were blinded.

RESULTS

At week 6, patients in the cilostazol group had significantly lower HAM-D score (p value= 0.015). General linear model repeated-measure analysis showed significant effect for treatment in improving MDD severity (p value <0.001). The remission rate at the study endpoint and number of responders at week 4 were significantly higher in the cilostazol group (p value= 0.047, p value= 0.032, respectively). The cilostazol group demonstrated a significantly shorter time to response. No significant difference was observed in treatment response at the study endpoint, and there were no serious adverse effects.

CONCLUSION

Our study supports safety and efficacy of cilostazol in treating MDD patients.

TRIAL REGISTRATION

This trial was registered at the Iranian registry of clinical trials (IRCT: www.irct.ir ; registration number: IRCT20090117001556N130).

Double-blind, randomized, placebo-controlled pilot study of the phosphodiesterase-3 inhibitor cilostazol as an adjunctive to antidepressants in patients with major depressive disorder

AIMS

Cilostazol (CLS) has shown antidepressant effect in cardiovascular patients, post-stroke depression, and animal models through its neurotrophic and antiinflammatory activities. Consequently, we aimed to investigate its safety and efficacy in patients with MDD by conducting double-blind, randomized, placebo-controlled pilot study.

METHODS

80 participants with MDD (DSM-IV criteria) and Hamilton Depression Rating Scale (HDRS) score >20 were treated with CLS 50 mg or placebo twice daily plus escitalopram (ESC) 20 mg once daily for six weeks. Patients were evaluated by HDRS scores (weeks 0, 2, 4, and 6). Serum levels of CREB1, BDNF, 5-HT, TNF-α, NF- κB, and FAM19A5 were assessed pre- and post-treatment.

RESULTS

Co-administration of CLS had markedly decreased HDRS score at all-time points compared to the placebo group (p < 0.001). Early improvement, response, and remission rates after 6 weeks were significantly higher in the CLS group (90%, 90%, 80%, respectively) than in the placebo group (25%, 65%, 50% respectively) (p < 0.001). Moreover, the CLS group was superior to the placebo group in modulation of the measured neurotrophic and inflammatory biomarkers.

CONCLUSION

CLS is safe and effective short-term adjunctive therapy in patients with MDD with no other comorbid conditions. Trial registration ID:NCT04069819.