Metabolic Effects of Antidepressant Treatment

What could be the reasons for not losing weight even after following a weight loss program?

INTRODUCTION

Approximately four million people worldwide die annually because of obesity. Weight loss is commonly recommended as a first-line therapy in overweight and obese patients. Although many individuals attempt to lose weight, not everyone achieves optimal success. Few studies point out that weight loss eventually slows down, stagnates or reverses in 85% of the cases.

RESEARCH QUESTION

What could be the reasons for not losing weight even after following a weight loss program?

METHODS

A scoping review of the literature was performed using weight loss-related search terms such as 'Obesity,' 'Overweight,' 'Lifestyle,' 'weight loss,' 'Basal Metabolism,' 'physical activity,' 'adherence,' 'energy balance,' 'Sleep' and 'adaptations. The search involved reference tracking and database and web searches (PUBMED, Science Direct, Elsevier, Web of Science and Google Scholar). Original articles and review papers on weight loss involving human participants and adults aged > 18 years were selected. Approximately 231 articles were reviewed, and 185 were included based on the inclusion criteria.

DESIGN

Scoping review.

RESULTS

In this review, the factors associated with not losing weight have broadly been divided into five categories. Studies highlighting each subfactor were critically reviewed and discussed. A wide degree of interindividual variability in weight loss is common in studies even after controlling for variables such as adherence, sex, physical activity and baseline weight. In addition to these variables, variations in factors such as previous weight loss attempts, sleep habits, meal timings and medications can play a crucial role in upregulating or downregulating the association between energy deficit and weight loss results.

CONCLUSION

This review identifies and clarifies the role of several factors that may hinder weight loss after the exploration of existing evidence. Judging the effectiveness of respective lifestyle interventions by simply observing the 'general behavior of the groups' is not always applicable in clinical practice. Each individual must be monitored and advised as per their requirements and challenges.

Lipids in Psychiatric Disorders: Functional and Potential Diagnostic Role as Blood Biomarkers

Lipids are a crucial component of the human brain, serving important structural and functional roles. They are involved in cell function, myelination of neuronal projections, neurotransmission, neural plasticity, energy metabolism, and neuroinflammation. Despite their significance, the role of lipids in the development of mental disorders has not been well understood. This review focused on the potential use of lipids as blood biomarkers for common mental illnesses, such as major depressive disorder, anxiety disorders, bipolar disorder, and schizophrenia. This review also discussed the impact of commonly used psychiatric medications, such as neuroleptics and antidepressants, on lipid metabolism. The obtained data suggested that lipid biomarkers could be useful for diagnosing psychiatric diseases, but further research is needed to better understand the associations between blood lipids and mental disorders and to identify specific biomarker combinations for each disease.

Effect of Vortioxetine in Comparison to Fluoxetine on Metabolic Parameters in Patients With Depressive Disorder: A Randomized Controlled Trial

Background Major depressive disorder (MDD) is a debilitating mood disorder that increases the risk of metabolic syndrome (MS), emphasizing the need for mental and physical health treatments. Although many studies have linked atypical antipsychotics to metabolic disturbances, there is limited evidence linking selective serotonin reuptake inhibitor use to MS. This study aimed to assess the risk of MS among patients with MDD who were administered vortioxetine and fluoxetine. Methodology This was a prospective, open-label, randomized controlled trial conducted in the psychiatry department. Using computer-generated random numbers, the physician assigned fluoxetine 20 mg or vortioxetine 10 mg and recorded MS parameters at baseline and each visit (4, 8, 12, 16, 20, and 24 weeks). This study was registered with CTRI (CTRI/2021/07/034892). Results A total of 122 participants were allocated randomly to the following two groups: group A (n = 60) and group B (n = 62). An independent-sample t-test showed a significant improvement in fasting plasma glucose (FPG) at week eight (p = 0.005), triglycerides (TGs) at week 16 (p = 0.005), high-density lipoprotein (HDL) at week 20 (p = 0.005), and waist circumference at week 24 (p = 0.005) in group A compared to group B. However, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were not significantly associated with either group (p = 0.126 and p = 0.793, respectively). Overall depression remission (Hamilton Depression Rating Scale (HAM-D)) and medication adherence rating scale scores were similar between groups (p = 0.337 and 0.325, respectively). Furthermore, most adverse drug reactions were possibly associated with the study drugs. Conclusions In comparison to group B, group A showed significant improvements in FPG, HDL, and waist circumference more effectively; however, both groups led to higher TG levels, with non-significant numerical improvements observed in SBP and DBP in both groups. In addition, both treatment groups reduced the HAM-D score and had a similar MDD remission rate.

Fluoxetine promotes immunometabolic defenses to mediate host-pathogen cooperation during sepsis

Selective serotonin reuptake inhibitors (SSRIs) are some of the most prescribed drugs in the world. While they are used for their ability to increase serotonergic signaling in the brain, SSRIs are also known to have a broad range of effects beyond the brain, including immune and metabolic effects. Recent studies have demonstrated that SSRIs are protective in animal models and humans against several infections, including sepsis and COVID-19, however the mechanisms underlying this protection are largely unknown. Here we mechanistically link two previously described effects of the SSRI fluoxetine in mediating protection against sepsis. We show that fluoxetine-mediated protection is independent of peripheral serotonin, and instead increases levels of circulating IL-10. IL-10 is necessary for protection from sepsis-induced hypertriglyceridemia and cardiac triglyceride accumulation, allowing for metabolic reprogramming of the heart. Our work reveals a beneficial "off-target" effect of fluoxetine, and reveals a protective immunometabolic defense mechanism with therapeutic potential.

The Potential Use of Monocyte-to-High-Density Lipoprotein Ratio as a Chronic Inflammatory Marker in Major Depressive Disorder

Background

Monocytes secrete pro-inflammatory and pro-oxidant cytokines as part of inflammatory reactions. High-density lipoproteins have anti-inflammatory and antioxidant effects. This study investigated the potential use of the monocyte-to-high-density lipoprotein ratio in the follow-up of major depressive disorder.

Methods

The study group was composed of patients with newly diagnosed or preexisting major depressive disorder who applied to a psychiatric clinic and did not receive antidepressant treatment in the last 2 weeks. These patients were tested for the monocyte-to-high-density lipoprotein ratio in the psychiatric outpatient clinic both in the first interview and at their follow-up at 2 months. The control group, on the other hand, consisted of subjects who presented to the checkup clinic without any complaints.

Results

The study included a total of 98 individuals aged between 18 and 62 years, including 66 women and 32 men. The proportion of women in the study group was higher than that in the control group (P = .002). Patients in the study group had higher first high-density lipoprotein levels than healthy controls (P = .026). Beck's Depression Inventory scores of the study group decreased significantly from the first to the second interview (P < .001). There was no significant correlation between the percentage of change in Beck's Depression Inventory scores and the percentage of change in the monocyte-to-high-density lipoprotein ratio (P = .271).

Conclusion

The high-density lipoprotein levels in healthy controls were not higher than those in the group with major depressive disorder; monocyte levels did not differ between the groups and the monocyte-to-high-density lipoprotein ratio was not superior to Beck's Depression Inventory and could not be used in prognosis.

Brain deficit patterns of metabolic illnesses overlap with those for major depressive disorder: A new metric of brain metabolic disease

Metabolic illnesses (MET) are detrimental to brain integrity and are common comorbidities in patients with mental illnesses, including major depressive disorder (MDD). We quantified effects of MET on standard regional brain morphometric measures from 3D brain MRI as well as diffusion MRI in a large sample of UK BioBank participants. The pattern of regional effect sizes of MET in non-psychiatric UKBB subjects was significantly correlated with the spatial profile of regional effects reported by the largest meta-analyses in MDD but not in bipolar disorder, schizophrenia or Alzheimer's disease. We used a regional vulnerability index (RVI) for MET (RVI-MET) to measure individual's brain similarity to the expected patterns in MET in the UK Biobank sample. Subjects with MET showed a higher effect size for RVI-MET than for any of the individual brain measures. We replicated elevation of RVI-MET in a sample of MDD participants with MET versus non-MET. RVI-MET scores were significantly correlated with the volume of white matter hyperintensities, a neurological consequence of MET and age, in both groups. Higher RVI-MET in both samples was associated with obesity, tobacco smoking and frequent alcohol use but was unrelated to antidepressant use. In summary, MET effects on the brain were regionally specific and individual similarity to the pattern was more strongly associated with MET than any regional brain structural metric. Effects of MET overlapped with the reported brain differences in MDD, likely due to higher incidence of MET, smoking and alcohol use in subjects with MDD.

Comparative metabolomic analysis in plasma and cerebrospinal fluid of humans and in plasma and brain of mice following antidepressant-dose ketamine administration

Subanesthetic-dose racemic (R,S)-ketamine (ketamine) produces rapid, robust, and sustained antidepressant effects in major depressive disorder (MDD) and bipolar disorder (BD) and has also been shown to effectively treat neuropathic pain, complex regional pain syndrome, and post-traumatic stress disorder (PTSD). However, to date, its mechanism of action remains unclear. Preclinical studies found that (2 R,6 R;2 S,6 S)-hydroxynorketamine (HNK), a major circulating metabolite of ketamine, elicits antidepressant effects similar to those of ketamine. To help determine how (2 R,6 R)-HNK contributes to ketamine's mechanism of action, an exploratory, targeted, metabolomic analysis was carried out on plasma and CSF of nine healthy volunteers receiving a 40-minute ketamine infusion (0.5 mg/kg). A parallel targeted metabolomic analysis in plasma, hippocampus, and hypothalamus was carried out in mice receiving either 10 mg/kg of ketamine, 10 mg/kg of (2 R,6 R)-HNK, or saline. Ketamine and (2 R,6 R)-HNK both affected multiple pathways associated with inflammatory conditions. In addition, several changes were unique to either the healthy human volunteers and/or the mouse arm of the study, indicating that different pathways may be differentially involved in ketamine's effects in mice and humans. Mechanisms of action found to consistently underlie the effects of ketamine and/or (2 R,6 R)-HNK across both the human metabolome in plasma and CSF and the mouse arm of the study included LAT1, IDO1, NAD+, the nitric oxide (NO) signaling pathway, and sphingolipid rheostat.

Lipid Biomarkers in Depression: Does Antidepressant Therapy Have an Impact?

Studies have revealed mixed results on how antidepressant drugs affect lipid profiles of patients with major depression disorder (MDD). Even less is known about how patients respond to a switch of antidepressant medication with respect to their metabolic profile. For this, effects of a switch in antidepressants medication on lipid markers were studied in MDD patients. 15 participants (females = 86.67%; males = 13.33%; age: 49.45 ± 7.45 years) with MDD and a prescribed switch in their antidepressant medication were recruited at a psychosomatic rehabilitation clinic. Participants were characterized (with questionnaires and blood samples) at admission to the rehabilitation clinic (baseline, T0) and followed up with a blood sample two weeks (T1) later. HDL, LDL, total cholesterol, and triglycerides were determined (T0), and their change analyzed (Wilcoxon test) at follow up (T1). Decrements in HDL (p = 0.041), LDL (p < 0.001), and total cholesterol (p < 0.001) were observed two weeks after a switch in antidepressant medication. Triglycerides showed no difference (p = 0.699). Overall, LDL, HDL, and total cholesterol are affected by a change in antidepressant drugs in patients with MDD. These observations are of clinical relevance for medical practitioners in the planning and management of treatment strategies for MDD patients.

Therapy Management of Metabolic Disorder Comorbidity With Depression

Depression is a common disease that seriously endangers the physical and mental health of human beings, and it often coexists with other metabolic disorders such as diabetes and cancer. There have been endless reports on the mechanism, prevention, and cure of comorbidity because of its high incidence and poor prognosis and the increased burden on the family and society. There may be a specific comorbid basis and causal relationship between depression and metabolic diseases. Depression in patients with metabolic disorders can be effectively alleviated through psychotherapy and medication. The timely and effective treatment of depression can significantly improve the quality of life of patients with metabolic disorders, reduce their psychological burden, and promote the effective treatment of metabolic diseases. This study reorganized the research progress on the management of metabolic disorder comorbidity with depression.

Untargeted Plasma Metabolomic Profiling in Patients with Major Depressive Disorder Using Ultra-High Performance Liquid Chromatography Coupled with Mass Spectrometry

Major depressive disorder (MDD) is a neuropsychiatric illness with an increasing incidence and a shortfall of efficient diagnostic tools. Interview-based diagnostic tools and clinical examination often lead to misdiagnosis and inefficient systematic treatment selection. Diagnostic and treatment monitoring biomarkers are warranted for MDD. Thus, the emerging field of metabolomics is a promising tool capable of portraying the metabolic repertoire of biomolecules from biological samples in a minimally invasive fashion. Herein, we report an untargeted metabolomic profiling performed in plasma samples of 11 MDD patients, at baseline (MDD1) and at 12 weeks following antidepressant therapy with escitalopram (MDD2), and in 11 healthy controls (C), using ultra-high performance liquid chromatography coupled with electrospray ionization-quadrupole-time of flight-mass spectrometry (UHPLC-QTOF-(ESI+)-MS). We found two putative metabolites ((phosphatidylserine PS (16:0/16:1) and phosphatidic acid PA (18:1/18:0)) as having statistically significant increased levels in plasma samples of MDD1 patients compared to healthy subjects. ROC analysis revealed an AUC value of 0.876 for PS (16:0/16:1), suggesting a potential diagnostic biomarker role. In addition, PS (18:3/20:4) was significantly decreased in MDD2 group compared to MDD1, with AUC value of 0.785.

Chronic fluoxetine treatment impairs motivation and reward learning by affecting neuronal plasticity in the central amygdala

BACKGROUND AND PURPOSE

The therapeutic effects of fluoxetine are believed to be due to increasing neuronal plasticity and reversing some learning deficits. Nevertheless, a growing amount of evidence shows adverse effects of this drug on cognition and some forms of neuronal plasticity.

EXPERIMENTAL APPROACH

To study the effects of chronic fluoxetine treatment, we combine an automated assessment of motivation and learning in mice with an investigation of neuronal plasticity in the central amygdala and basolateral amygdala. We use immunohistochemistry to visualize neuronal types and perineuronal nets, along with DI staining to assess dendritic spine morphology. Gel zymography is used to test fluoxetine's impact on matrix metalloproteinase-9, an enzyme involved in synaptic plasticity.

KEY RESULTS

We show that chronic fluoxetine treatment in non-stressed mice increases perineuronal nets-dependent plasticity in the basolateral amygdala, while impairing MMP-9-dependent plasticity in the central amygdala. Further, we illustrate how the latter contributes to anhedonia and deficits of reward learning. Behavioural impairments are accompanied by alterations in morphology of dendritic spines in the central amygdala towards an immature state, most likely reflecting animals' inability to adapt. We strengthen the link between the adverse effects of fluoxetine and its influence on MMP-9 by showing that behaviour of MMP-9 knockout animals remains unaffected by the drug.

CONCLUSION AND IMPLICATIONS

Chronic fluoxetine treatment differentially affects various forms of neuronal plasticity, possibly explaining its opposing effects on brain and behaviour. These findings are of immediate clinical relevance since reported side effects of fluoxetine pose a potential threat to patients.

Antidepressants: bleeding or thrombosis?

The contribution of depression to the pathogenesis of cardiovascular disease includes autonomic disturbances, endothelial dysfunction, inflammation, smoking, sedentary lifestyle, carbohydrate craving, and impaired fibrinolysis. There is evidence that serotonergic antidepressants (selective serotonin reuptake inhibitors and serotonin and noradrenaline reuptake inhibitors) restore the fibrinolytic profile. Contrary to common belief, such antidepressants do not affect platelet aggregation induced by adenosine diphosphate or adrenaline but reduce platelet adhesion to collagen. Since platelet collagen receptor glycoprotein VI binds to fibrin, it is possible that fibrinolytic properties of serotonergic antidepressants could impair platelet adhesion to collagen. The profibrinolytic and antiplatelet properties of serotonergic antidepressants help explain the increased risk of gastrointestinal, intracranial, and surgical bleeding in patients using these medications. Studies evaluating the impact of antidepressants on thrombotic and cardiovascular risk have yielded contradictory results. Corroborating the hypothesis that serotonergic antidepressants have profibrinolytic and antiplatelet properties, some authors showed that these medications prevent both cardiovascular and thromboembolic events. Others showed an increased risk of ischemic stroke, cardiac events and thromboembolic disease. Silent brain infarction may present in some elders with depressive symptoms, so it is presumed that antidepressants are prescribed for subclinical stroke patients. Another explanation for the increased risk of cardiovascular and thromboembolic events reported by some authors in individuals taking antidepressants includes antidepressant side effects such as sedation and weight gain and depression comorbidities such as anxiety, obesity and hyperhomocysteinemia. In conclusion, we suggest that serotonergic antidepressants be considered weak anticoagulants. We also suggest that depressed patients with comorbidities increasing the risk of cardiovascular and thromboembolic disease be recommended to follow a balanced diet and engage in physical activity, such as daily walking.

Differential effects of psychotropic drugs on microbiome composition and gastrointestinal function

RATIONALE

Growing evidence supports a role for the microbiota in regulating gut-brain interactions and, thus, psychiatric disorders. Despite substantial scientific efforts to delineate the mechanism of action of psychotropic medications at a central nervous system (CNS) level, there remains a critical lack of understanding on how these drugs might affect the microbiota and gut physiology.

OBJECTIVES

We investigated the antimicrobial activity of psychotropics against two bacterial strain residents in the human gut, Lactobacillus rhamnosus and Escherichia coli. In addition, we examined the impact of chronic treatment with these drugs on microbiota and intestinal parameters in the rat.

RESULTS

In vitro fluoxetine and escitalopram showed differential antimicrobial effects. Lithium, valproate and aripiprazole administration significantly increased microbial species richness and diversity, while the other treatments were not significantly different from controls. At the genus level, several species belonging to Clostridium, Peptoclostridium, Intestinibacter and Christenellaceae were increased following treatment with lithium, valproate and aripiprazole when compared to the control group. Animals treated with escitalopram, venlafaxine, fluoxetine and aripiprazole exhibited an increased permeability in the ileum.

CONCLUSIONS

These data show that psychotropic medications differentially influence the composition of gut microbiota in vivo and that fluoxetine and escitalopram have specific antimicrobial activity in vitro. Interestingly, drugs that significantly altered gut microbial composition did not increase intestinal permeability, suggesting that the two factors are not causally linked. Overall, unravelling the impact of psychotropics on gastrointestinal and microbiota measures offers the potential to provide critical insight into the mechanism of action and side effects of these medications.

Severe Depressive Episode with Psychotic Symptoms and Type 2 Diabetes: A 2010-2017 Longitudinal Study

BACKGROUND There have been few studies published on the prevalence of severe depressive episode in people with type 2 diabetes (T2DM) or its role in adherence to dietary recommendations. We examined the Polish National Health Fund (NFZ) database estimates of all medical visits from 2010 to 2017 to determine the trend and the epidemiology of severe depressive episode in T2DM. MATERIAL AND METHODS The NFZ database was used. We defined the T2DM group diagnosed with both T2DM and severe depressive episode according to the ICD-10 codes. The annual prevalence of severe depressive episode was estimated according to the T2DM diagnosis status, and the age groups were stratified into 8 groups. RESULTS Relative risk for depression (regardless of severity of symptoms) in T2DM is 1.347 [95%CI: 1.342-1.353]. The frequency trend of severe depressive episode with or without psychotic symptoms remains relatively stable. In the case of mild and moderate depressive episode, a downward trend was noted, but they are still the most frequent mood disorders diagnosed. Patients with T2DM aged 20 to 40, for whom the peak of coexistence of these illnesses was noted, are the group particularly vulnerable to depression. Depression also remains on a relatively high but stable level for patients over 60 years of age. CONCLUSIONS The coexistence of depressive episodes in T2DM is a key challenge for medicine and public health. Measures aimed at early identification of patients with T2DM prone to depression need to be taken. Creating multidisciplinary care teams in diabetes management is also necessary.

The Impact of Prolonged, Selective, Serotonin Reuptake Inhibitor Treatment on Serum Lipid and Glucose Levels in Children and Adolescents: A Preliminary Prospective Study

OBJECTIVES

Treatment with selective serotonin reuptake inhibitors (SSRIs) is common and is considered safe and effective in the treatment of anxiety and depressive disorders in pediatric populations. SSRI administration, however, is associated with adverse metabolic effects. The aim of this preliminary study was to evaluate the possible influence of a 6-month SSRI treatment on metabolic parameters in children and adolescents with depressive and/or anxiety disorders.

METHODS

Metabolic parameters (glucose, cholesterol, triglycerides, low-density lipoprotein [LDL], and high-density lipoprotein [HDL]) were monitored in 22 children and adolescents (16 boys and 6 girls, aged 8-18 years) at baseline and after 6 months of SSRI treatment for depression and/or anxiety.

RESULTS

Six months of SSRI treatment did not affect serum glucose, cholesterol, or triglycerides significantly, but a tendency (p = 0.06) toward elevation in serum LDL accompanied by a parallel reduction in HDL levels was detected.

CONCLUSION

It appears that the 6-month SSRI treatment is metabolically safe in children and adolescents and does not affect the glucose or lipid profile. Long-term large-scale studies in pediatric populations focusing on the possible impact of long-term SSRI treatment (>6 months) on metabolic parameters are warranted.

Fluoxetine induces lipid metabolism abnormalities by acting on the liver in patients and mice with depression

Depressive disorders are frequently managed with long-term use of antidepressant medication. Fluoxetine (FLX) is the first selective serotonin reuptake inhibitor to be widely available for the treatment of depression. The present study focuses on the effects and mechanisms of the lipid metabolism abnormalities caused by FLX in patients and in a mouse model of depression. Depression severity was assessed by the Hamilton Depression Scale (HAMD). Triglyceride (TG), cholesterol (TC) and low-density lipoprotein (LDL) serum levels were assessed in 28 patients with depression, aged 31.2±3.3 years, treated with FLX (20 to 60 mg/day) for 8 weeks. Meanwhile, the serum levels of other lipid metabolism-related parameters, such as high-density lipoprotein (HDL), apolipoprotein A1 (APOA1) and apolipoprotein B (ApoB), were also determined. The infiuence of FLX on the hepatic lipid profile and hepatic gene expression of both lipogenic and lipolytic enzymes was evaluated in a mouse model of depression treated with FLX (10 mg·kg^-1·d^-1, ip) for 4 weeks. We showed that the serum TG, TC and LDL levels were significantly increased in patients with depression after FLX treatment. The elevation in serum TG levels in the patients was not affected by gender or family history. FLX treatment did not significantly alter serum HDL, APOA1 or APOB levels in the patients. We further demonstrated in mice with depression that FLX treatment increased the hepatic TG level by increasing the expression of lipogenic enzymes and decreasing the expression of lipolytic enzymes in the liver. Antidepressive therapy with FLX is associated with lipid metabolism abnormalities, which are in part mediated by disturbances in hepatic lipid metabolism homeostasis. The findings contribute to the uncovering of metabolic adverse reactions in the pharmacological therapy of depression.

Adrenal activity and metabolic risk during randomized escitalopram or placebo treatment in PCOS

BACKGROUND/AIMS

Polycystic ovary syndrome (PCOS) is associated with insulin resistance, adrenal hyperactivity and decreased mental health. We aimed to investigate the changes in adrenal activity, metabolic status and mental health in PCOS during treatment with escitalopram or placebo.

METHODS

Forty-two overweight premenopausal women with PCOS and no clinical depression were randomized to 12-week SSRI (20 mg escitalopram/day, n = 21) or placebo (n = 21). Patients underwent clinical examination, fasting blood samples, adrenocorticotroph hormone (ACTH) test, 3-h oral glucose tolerance test (OGTT) and filled in questionnaires regarding mental health and health-related quality of life (HRQoL): WHO Well-Being Index (WHO-5), Major Depression Inventory (MDI), Short Form 36 (SF-36) and PCOS questionnaire.

RESULTS

Included women were aged 31 (6) years (mean (s.d.)) and had body mass index (BMI) 35.8 (6.5) kg/m² and waist 102 (12) cm. Escitalopram was associated with increased waist (median (quartiles) change 1 (0; 3) cm), P = 0.005 vs change during placebo and increased cortisol levels (cortisol 0, cortisol 60, peak cortisol and area under the curve for cortisol during ACTH test), all P  < 0.05 vs changes during placebo. Escitalopram had no significant effect on measures of insulin sensitivity, insulin secretion, fasting lipids, mental health or HRQoL.

CONCLUSION

Waist circumference and cortisol levels increased during treatment with escitalopram in women with PCOS and no clinical depression, whereas metabolic risk markers, mental health and HRQol were unchanged.