Effects of second generation antipsychotics on leptin and ghrelin

Comparative predictive efficacy of atherogenic indices on metabolic syndrome in patients with schizophrenia

BACKGROUND

Schizophrenia patients endure high risks of metabolic syndrome and related cardiovascular mortality. Evidence on comparing detective power among atherogenic indices of the metabolic syndrome in schizophrenia patients with antipsychotics treatment is still lacking.

METHOD

We recruited 128 schizophrenia patients and collected blood samples to determine plasma levels of fasting glucose, total cholesterol, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol. Five components of metabolic syndrome were assessed. Atherogenic indices, such as atherogenic index of plasma (AIP), atherogenic coefficient (AC), Castelli's risk index-I (CRI-I) and Castelli's risk index-II (CRI-II), were calculated. The area under the receiver operating characteristics curve (AUC) and regression analysis were adopted to compare the detective power of each atherogenic index for metabolic syndrome. The optimal cutoff points using maximization of Youden's index and the positive likelihood ratios were calculated.

RESULTS

51 (39.8 %) had metabolic syndrome. AIP (0.2 ± 0.2 vs. 0.6 ± 0.2), AC (2.5 ± 0.9 vs. 3.4 ± 0.9), CRI-I (3.5 ± 0.9 vs. 4.4 ± 0.9,) and CRI-II (2.1 ± 0.7 vs. 2.6 ± 0.7) were higher in the group with metabolic syndrome (all p < 0.001). AIP had the highest AUC (0.845, 95 % CI: 0.770, 0.920). The optimal cut-off point of AIP to predict metabolic syndrome was 0.4 with the corresponding sensitivity 83.7 %, specificity 80.3 %, and positive likelihood ratio 4.2. Regression analysis revealed that only AIP significantly correlated with the metabolic syndrome (p < 0.001).

CONCLUSION

Among atherogenic indices, only AIP has superior discrimination for detecting metabolic syndrome in schizophrenia with antipsychotics treatment.

Metabolic effects of atypical antipsychotics: Molecular targets

Atypical antipsychotics (AAPs) are commonly prescribed drugs in the treatment of schizophrenia, bipolar disorder and other mental diseases with psychotic traits. Although the use of AAPs is associated with beneficial effects in these patients, they are also associated with undesired metabolic side effects, including metabolic syndrome (MetS). MeS is defined by the presence of metabolic abnormalities such as large waist circumference, dyslipidemia, fasting hyperglycemia and elevated blood pressure, which predispose to type 2 diabetes (T2D) and cardiovascular disease. In this review, the molecular and cellular mechanisms involved in these undesired metabolic abnormalities induced by AAPs are described. These mechanisms are complex as AAPs have multiple cellular targets which significantly affect the activities of several hormones and neuromodulators. Additionally, AAPs affect all the relevant metabolic organs, namely the liver, pancreas, adipose tissue, skeletal muscle and intestine, and the central and peripheral nervous system as well. A better understanding of the molecular targets linking AAPs with MetS and of the mechanisms responsible for clinically different side effects of distinct AAPs is needed. This knowledge will help in the development of novel AAPs with less adverse effects as well as of adjuvant therapies to patients receiving AAPs.

Impact of clozapine monotherapy on gut microbiota and metabolism in people with schizophrenia

Background

Clozapine is considered one of the most effective antipsychotic drugs, but it is most likely to cause metabolic abnormalities. Researchers have studied the causes of metabolic abnormalities caused by clozapine from multiple perspectives, but the reasons remain unclear.

Purpose

Characterize the gut microbiota of people with schizophrenia taking clozapine, exploring the association between gut microbiota and glucose lipid metabolic markers in schizophrenia patients taking clozapine.

Research design

Sixty-one long-term inpatients with schizophrenia in clozapine monotherapy were selected as study subjects. We got four subgroups by sex and the presence of metabolic syndrome.

Data analysis

16s analysis technology was applied at the genus level to determine the classification of gut microbiota. Then we compared the characteristics of gut microbiota and the association of gut microbiota with glucose lipid metabolic markers in each group.

Findings

We found differences in the diversity of gut microbiota among groups. The association between gut microbiota and glucose lipid metabolic markers was complicated. Gender was an important differentiating factor. Oscillibacter has a low abundance. However, it was the only genus associated with glycemic or lipids in each group. Among metabolic syndromes, Gemmiger was positively correlated with most lipids in females but negatively correlated in males, showing gender differences. In female non-metabolic syndromes, Bifidobacterium lost its probiotic character; instead, showing pathogenicity, which has strong positive correlations with fasting blood glucose and low-density lipoprotein but negative correlations with Apolipoprotein A1. Maybe schizophrenia, taking clozapine, and gender factors influenced the gut microbiota, which complicated our findings. The significance of the results remains to be determined by in-depth studies.

Peripubertal Alterations of Leptin Levels in Patients with Autism Spectrum Disorder and Elevated or Normal Body Weight

Leptin, which plays a key role in energy homeostasis, is known as a neurotrophic factor possibly linking nutrition and neurodevelopment. Available data on the association between leptin and autism spectrum disorder (ASD) are confusing. The aim of this study was to explore whether plasma levels of leptin in pre- and post-pubertal children with ASD and/or overweightness/obesity differ from those of BMI- and age-matched healthy controls. Leptin levels were determined in 287 pre-pubertal children (mean age 8.09 years), classified as follows: ASD with overweightness/obesity (ASD+/Ob+); ASD without overweightness/obesity (ASD+/Ob-); non-ASD with overweightness/obesity (ASD-/Ob+); non-ASD without overweightness/obesity (ASD-/Ob-). The assessment was repeated in 258 of the children post-pubertally (mean age 14.26 years). There were no significant differences in leptin levels either before or after puberty between ASD+/Ob+ and ASD-/Ob+ or between ASD+/Ob- and ASD-/Ob-, although there was a strong trend toward significance for higher pre-pubertal leptin levels in ASD+/Ob- than in ASD-/Ob-. Post-pubertal leptin levels were significantly lower than pre-pubertal levels in ASD+/Ob+, ASD-/Ob+, and ASD+/Ob- and higher in ASD-/Ob-. Leptin levels, elevated pre-pubertally in the children with overweightness/obesity as well as in children with ASD and normal BMI, decrease with age, in contrast to the increasing leptin levels in healthy controls.

Gut Microbiota and Time-Restricted Feeding/Eating: A Targeted Biomarker and Approach in Precision Nutrition

Each individual has a unique gut microbiota; therefore, the genes in our microbiome outnumber the genes in our genome by about 150 to 1. Perturbation in host nutritional status influences gut microbiome composition and vice versa. The gut microbiome can help in producing vitamins, hormones, and other active metabolites that support the immune system; harvest energy from food; aid in digestion; protect against pathogens; improve gut transit and function; send signals to the brain and other organs; oscillate the circadian rhythm; and coordinate with the host metabolism through multiple cellular pathways. Gut microbiota can be influenced by host genetics, medications, diet, and lifestyle factors from preterm to aging. Aligning with precision nutrition, identifying a personalized microbiome mandates the provision of the right nutrients at the right time to the right patient. Thus, before prescribing a personalized treatment, it is crucial to monitor and count the gut flora as a focused biomarker. Many nutritional approaches that have been developed help in maintaining and restoring an optimal microbiome such as specific diet therapy, nutrition interventions, and customized eating patterns. One of these approaches is time-restricted feeding/eating (TRF/E), a type of intermittent fasting (IF) in which a subject abstains from food intake for a specific time window. Such a dietary modification might alter and restore the gut microbiome for proper alignment of cellular and molecular pathways throughout the lifespan. In this review, we have highlighted that the gut microbiota would be a targeted biomarker and TRF/E would be a targeted approach for restoring the gut-microbiome-associated molecular pathways such as hormonal signaling, the circadian system, metabolic regulators, neural responses, and immune-inflammatory pathways. Consequently, modulation of the gut microbiota through TRF/E could contribute to proper utilization and availability of the nutrients and in this way confer protection against diseases for harnessing personalized nutrition approaches to improve human health.

Increased growth hormone secretagogue receptor-1a (GHSR-1a) in hypothalamus during olanzapine treatment in rats

Weight gain is the one of the most important factors which increases global burden of psychiatric disorder. Second-generation antipsychotics, olanzapine (Olz) and valproic acid (Vpa) in particular, are held responsible for weight gain. However, it is still uncertain how these drugs cause this. Thus, the rats selected for the experiment were randomly divided into 3 groups. The 1st group received only 0.5 ml saline solution intraperitoneally (n = 20, control group); the second group was given 200 mg / kg Vpa intraperitoneally (n = 20, Vpa group) and 2 mg / kg Olz was given intraperitoneally to the 3rd group (n = 20, Olz group) between 8 and 10 am for 30 days. We examined serum leptin, adiponectin, resistin, TNF-α, IL-6, ghrelin level and, the amount of ghrelin secreting cells in the stomach and growth hormone secretagogue receptor-1a (GHSR-1a, ghrelin receptor) expression in the hypothalamus. The hypothalamic GHS-1a receptor index was significantly higher in the Olz group compared with the control group and Vpa group (p = 0.036 and p = 0.016 respectively). Ghrelin immune positive cell index in stomach was statistically significantly lower in the Vpa group compared with the control and Olz groups (p = 0.028 and p = 0.013 respectively) There was no difference between the groups in terms of serum leptin, resistin, IL-6 and ghrelin levels. In the Vpa group, a statistically significant increase was found in serum adiponectin level compared with both the control group and the Olz group (p = 0009 and p = 0024 respectively) and, significant decrease was found in serum TNF-α level compared to Olz group (p = 0007). In conclusion, we found that the main cause of weight gain in Olz use was the increase in the number of hypothalamic ghrelin receptors. Investigating the mechanism by which Olz increases the number of ghrelin receptors may help to develop effective treatment strategies in preventing obesity in psychiatric patients.

Understanding the Role of the Gut Microbiome in Brain Development and Its Association With Neurodevelopmental Psychiatric Disorders

The gut microbiome has a tremendous influence on human physiology, including the nervous system. During fetal development, the initial colonization of the microbiome coincides with the development of the nervous system in a timely, coordinated manner. Emerging studies suggest an active involvement of the microbiome and its metabolic by-products in regulating early brain development. However, any disruption during this early developmental process can negatively impact brain functionality, leading to a range of neurodevelopment and neuropsychiatric disorders (NPD). In this review, we summarize recent evidence as to how the gut microbiome can influence the process of early human brain development and its association with major neurodevelopmental psychiatric disorders such as autism spectrum disorders, attention-deficit hyperactivity disorder, and schizophrenia. Further, we discuss how gut microbiome alterations can also play a role in inducing drug resistance in the affected individuals. We propose a model that establishes a direct link of microbiome dysbiosis with the exacerbated inflammatory state, leading to functional brain deficits associated with NPD. Based on the existing research, we discuss a framework whereby early diet intervention can boost mental wellness in the affected subjects and call for further research for a better understanding of mechanisms that govern the gut-brain axis may lead to novel approaches to the study of the pathophysiology and treatment of neuropsychiatric disorders.

Gut microbiota: An intermediary between metabolic syndrome and cognitive deficits in schizophrenia

Gut microbiome interacts with the central nervous system tract through the gut-brain axis. Such communication involves neuronal, endocrine, and immunological mechanisms, which allows for the microbiota to affect and respond to various behaviors and psychiatric conditions. In addition, the use of atypical antipsychotic drugs (AAPDs) may interact with and even change the abundance of microbiome to potentially cause adverse effects or aggravate the disorders inherent in the disease. The regulate effects of gut microbiome has been described in several psychiatric disorders including anxiety and depression, but only a few reports have discussed the role of microbiota in AAPDs-induced Metabolic syndrome (MetS) and cognitive disorders. The following review systematically summarizes current knowledge about the gut microbiota in behavior and psychiatric illness, with the emphasis of an important role of the microbiome in the metabolism of schizophrenia and the potential for AAPDs to change the gut microbiota to promote adverse events. Prebiotics and probiotics are microbiota-management tools with documented efficacy for metabolic disturbances and cognitive deficits. Novel therapies for targeting microbiota for alleviating AAPDs-induced adverse effects are also under fast development.

A Focused Review of the Metabolic Side-Effects of Clozapine

The second generation antipsychotic drug clozapine represents the most effective pharmacotherapy for treatment-resistant psychosis. It is also associated with low rates of extrapyramidal symptoms and hyperprolactinemia compared to other antipsychotic drugs. However, clozapine tends to be underutilized in clinical practice due to a number of disabling and serious side-effects. These are characterized by a constellation of metabolic side-effects which include dysregulation of glucose, insulin, plasma lipids and body fat. Many patients treated with clozapine go on to develop metabolic syndrome at a higher rate than the general population, which predisposes them for Type 2 diabetes mellitus and cardiovascular disease. Treatments for the metabolic side-effects of clozapine vary in their efficacy. There is also a lack of knowledge about the underlying physiology of how clozapine exerts its metabolic effects in humans. In the current review, we focus on key studies which describe how clozapine affects each of the main symptoms of the metabolic syndrome, and cover some of the treatment options. The clinical data are then discussed in the context of preclinical studies that have been conducted to identify the key biological substrates involved, in order to provide a better integrated overview. Suggestions are provided about key areas for future research to better understand how clozapine causes metabolic dysregulation.

Metabolomic profiles associated with a mouse model of antipsychotic-induced food intake and weight gain

Antipsychotic drugs (AP) are used to treat a multitude of psychiatric conditions including schizophrenia and bipolar disorder. However, APs also have metabolic side effects including increased food intake and body weight, but the underlying mechanisms remain unknown. We previously reported that minocycline (MINO) co-treatment abrogates olanzapine (OLZ)-induced hyperphagia and weight gain in mice. Using this model, we investigated the changes in the pharmacometabolome in the plasma and hypothalamus associated with OLZ-induced hyperphagia and weight gain. Female C57BL/6 mice were divided into groups and fed either i) control, CON (45% fat diet) ii) CON + MINO, iii) OLZ (45% fat diet with OLZ), iv) OLZ + MINO. We identified one hypothalamic metabolite indoxylsulfuric acid and 389 plasma metabolites (including 19 known metabolites) that were specifically associated with AP-induced hyperphagia and weight gain in mice. We found that plasma citrulline, tricosenoic acid, docosadienoic acid and palmitoleic acid were increased while serine, asparagine and arachidonic acid and its derivatives were decreased in response to OLZ. These changes were specifically blocked by co-treatment with MINO. These pharmacometabolomic profiles associated with AP-induced hyperphagia and weight gain provide candidate biomarkers and mechanistic insights related to the metabolic side effects of these widely used drugs.

Correlation between vaspin and PANSS scores in schizophrenia patients with obesity

OBJECTIVE

Metabolic abnormalities such as diabetes, dyslipidemia, abdominal obesity, metabolic syndrome, and abnormal levels of plasma adipokines have been observed in patients with schizophrenia. This study aimed to investigate the differences and correlations of plasma vaspin levels with metabolic parameters in patients with schizophrenia and to compare with healthy controls.

METHOD

We measured plasma levels of vaspin and metabolic parameters of 100 patients with schizophrenia and 95 healthy controls. Patients with schizophrenia were evaluated with the Positive and Negative Syndrome Scale (PANSS) and The Global Assessment of Functioning.

RESULTS

Mean levels of body mass index, waist circumference, triglyceride, and low-density lipoprotein cholesterol of the patients were statistically higher than those of the healthy controls (p = 0.002, p < 0.001, p = 0.03, and p = 0.002, respectively). Plasma levels of vaspin were 0.96 ± 0.73 ng/ml in patients with schizophrenia and 0.29 ± 0.15 ng/ml in the healthy controls (p < 0.001). Plasma vaspin levels were statistically higher in patients with schizophrenia than healthy controls both in groups with and without metabolic syndrome and obesity (p < 0.001). Plasma vaspin levels showed a positive correlation with triglyceride in patients with schizophrenia (r = 0.26, p = 0.007). There were positive correlations between vaspin and PANSS scores in schizophrenia patients with obesity (PANSS Positive: r = 0.42, p = 0.01; PANSS Negative: r = 0.42, p = 0.01; PANSS General: r = 0.43, p = 0.01; PANSS Total: r = 0.47, p = 0.006).

CONCLUSIONS

Our study showed a significant relationship and positive correlation between vaspin and PANSS scores in schizophrenia patients with obesity. Vaspin may play an important role in the metabolic processes of patients with schizophrenia.

Leptin and psychiatric illnesses: does leptin play a role in antipsychotic-induced weight gain?

Antipsychotic-induced weight gain is the most prevalent somatic adverse event occurring in patients treated by antipsychotics, especially atypical antipsychotics. It is of particular interest because of its repercussion on cardiovascular morbidity and mortality especially now that the use of second-generation antipsychotics has been extended to other mental health illnesses such as bipolar disorders and major depressive disorder. The mechanism underlying antipsychotics-induced weight gain is still poorly understood despite a significant amount of work on the topic. Recently, there has been an on-going debate of tremendous research interest on the relationship between antipsychotic-induced weight gain and body weight regulatory hormones such as leptin. Given that, researchers have brought to light the question of leptin's role in antipsychotic-induced weight gain. Here we summarize and discuss the existing evidence on the link between leptin and weight gain related to antipsychotic drugs, especially atypical antipsychotics.

The effects of antipsychotic medications on microbiome and weight gain in children and adolescents

BACKGROUND

Atypical antipsychotics, also known as second-generation antipsychotics, are commonly prescribed as treatment for psychotic disorders in adults, as well as in children and adolescents with behavioral problems. However, in many cases, second-generation antipsychotics have unwanted side effects, such as weight gain, potentially further increasing risk for morbidities including obesity, diabetes, and cardiovascular disease. While various mechanisms for this weight gain have been proposed, including effects on metabolic hormone signaling, recent evidence points to the importance of the gut microbiome in this process. The microbial communities residing within the gut are affected by second-generation antipsychotics and can confer weight gain.

MAIN TEXT

This review summarizes recent findings and presents data linking second-generation antipsychotics, gut microbiota alterations and weight gain. The review focuses on children and adolescent populations, which have not previously received much attention, but are of great interest because they may be most vulnerable to gut microbiome changes and may carry long-term metabolic effects into adulthood.

CONCLUSIONS

We present correlations between second-generation antipsychotics, gut microbiota alterations and weight gain, and suggest some mechanisms that may link them. A better understanding of the underlying mechanisms may lead to the design of improved treatments for psychotic disorders with fewer harmful side effects.

Differential expression of the ghrelin-related mRNAs GHS-R1a, GHS-R1b, and MBOAT4 in Japanese patients with schizophrenia

OBJECTIVES

Ghrelin regulates appetite and also plays important roles in cognition and may be involved in vulnerability to SCZ.

METHODS

In this study, we measured mRNA expression of the ghrelin-related molecules, growth hormone secretagogue receptor 1a (GHS-R1a) and 1b (GHS-R1b), and the ghrelin activator, membrane bound O-acyltransferase 4 (MBOAT4). Peripheral leukocytes from Japanese patients with SCZ (n = 49; 23 males, 26 females; age = 61.8 ± 13.3 years) and controls (n = 50; 25 males, 25 females; age = 62.0 ± 14.3 years) were recruited according to their clinical information. We also studied the DNA methylation rates of these genes in DNA from leukocytes.

RESULTS

The mRNA expression of GHS-R1a was significantly decreased in SCZ (SCZ vs. control: 0.35 ± 0.081 vs. 1.00 ± 0.059, respectively, p = 0.007), but expression levels of GHS-R1b and MBOAT4 were significantly increased in SCZ (SCZ vs. control: 2.02 ± 0.91 vs. 1.00 ± 0.32, p = 0.023, 1.37 ± 0.21 vs. 1.00 ± 0.11, respectively, p = 0.014). No differences in methylation rates for any genes were found.

CONCLUSION

We conclude that opposite expression of GHS-R1a and GHS-R1b, and elevated MBOAT4 mRNA expression may reflect the mechanisms of SCZ.

The atypical antipsychotic, olanzapine, potentiates ghrelin-induced receptor signaling: An in vitro study with cells expressing cloned human growth hormone secretagogue receptor

The growth hormone secretagogue receptor (GHS-R) belongs to Gαq-coupled G protein-coupled receptor (GPCR) that mediates growth hormone release, food intake, appetite, glucose metabolism and body composition. Ghrelin has been identified as an endogenous ligand for GHS-R, and it is the only orexigenic peptide found in the peripheral organs. Olanzapine, an atypical antipsychotic agent that binds to and inhibits the activation of GPCR for several neurotransmitters, has metabolic side effects such as excessive appetite and weight gain. Recently, studies have revealed that the orexigenic mechanism of olanzapine is mediated via GHS-R signaling, although the precise mechanisms have not been clarified. In this study, we investigated the effect of olanzapine on ghrelin-mediated GHS-R signaling by using an electrical impedance-based receptor biosensor assay system (CellKey™). Olanzapine at concentrations of 10(-7) and 10(-6)mol/L enhanced ghrelin-induced (10(-10)-10(-8)mol/L) GHS-R activation. A Ca(2+) imaging assay revealed that olanzapine (10(-7) and 10(-6)mol/L) enhanced ghrelin (10(-7) M)-induced GHS-R activity. In contrast, haloperidol (an antipsychotic agent) failed to enhance this ghrelin-mediated GHS-R activation, as demonstrated by both the CellKey™ and Ca(2+) imaging assays. Together, these results suggest that olanzapine, but not haloperidol, promotes appetite by enhancing ghrelin-mediated GHS-R signaling.

Are leptin levels increased among people with schizophrenia versus controls? A systematic review and comparative meta-analysis

OBJECTIVE

Leptin may play a role in the pathophysiology of schizophrenia and it remains unclear if levels are raised compared to controls. Therefore, we performed a systematic review and meta-analysis comparing leptin levels among people with schizophrenia and controls.

METHOD

Two authors independently searched major electronic databases from inception until June 2015 for studies measuring blood leptin levels among people with schizophrenia and controls. Random effects meta-analysis calculating hedges g and 95% confidence intervals (CI) and meta-regression analyses were conducted.

RESULTS

Twenty-seven articles representing 1674 individuals with schizophrenia (34.6 ± 6.8 years, 55% male (0-100%), BMI 25.2 ± 3.1) and 2033 controls (33.9 ± 7.0 years, 51% male (0-100%), BMI=24.1 ± 2.1) were included. Across all studies, leptin levels may be marginally higher in schizophrenia (g=0.164, 95% CI -0.014-0.341, p=0.07, Q=217, p<0.01), particularly when one outlier was removed (g=0.196, 95% CI 0.210-0.370, p=0.02) and when we included the smallest effect size from studies with multiple comparisons (g=0.318, 95% CI 0.125-0.510, p=0.001). Leptin levels were higher in multi-episode schizophrenia (g=0.245, 95% CI 0.058-0.433, p=0.01) and females (g=0.557 95% CI 0.16-0.954, p=0.006). Subgroup analyses revealed leptin levels may be higher in participants taking second-generation antipsychotics compared to controls. Multivariate meta-regression demonstrated a lower percentage of males (β=-0.0064, 95% CI -0.0129 to -0.0002, p=0.05), but not BMI, moderated the results.

CONCLUSION

Our results suggest that schizophrenia is associated with increased blood leptin levels compared to controls, which may not be entirely attributable to antipsychotic medication or BMI. Other illness related and lifestyle choices may play a pivotal role.

Influence of MCHR2 and MCHR2-AS1 Genetic Polymorphisms on Body Mass Index in Psychiatric Patients and In Population-Based Subjects with Present or Past Atypical Depression

Obesity development during psychotropic treatments represents a major health issue in psychiatry. Melanin-concentrating hormone receptor 2 (MCHR2) is a central receptor involved in energy homeostasis. MCHR2 shares its promoter region with MCHR2-AS1, a long antisense non-coding RNA. The aim of this study was to determine whether tagging single nucleotide polymorphisms (tSNPs) of MCHR2 and MCHR2-AS1 are associated with the body mass index (BMI) in the psychiatric and in the general population. The influence of MCHR2 and MCHR2-AS1 tSNPs on BMI was firstly investigated in a discovery psychiatric sample (n₁ = 474). Positive results were tested for replication in two other psychiatric samples (n₂ = 164, n₃ = 178) and in two population-based samples (CoLaus, n₄ = 5409; GIANT, n₅ = 113809). In the discovery sample, TT carriers of rs7754794C>T had 1.08 kg/m² (p = 0.04) lower BMI as compared to C-allele carriers. This observation was replicated in an independent psychiatric sample (-2.18 kg/m²; p = 0.009). The association of rs7754794C>T and BMI seemed stronger in subjects younger than 45 years (median of age). In the population-based sample, a moderate association was observed (-0.17 kg/m²; p = 0.02) among younger individuals (<45y). Interestingly, this association was totally driven by patients meeting lifetime criteria for atypical depression, i.e. major depressive episodes characterized by symptoms such as an increased appetite. Indeed, patients with atypical depression carrying rs7754794-TT had 1.17 kg/m² (p = 0.04) lower BMI values as compared to C-allele carriers, the effect being stronger in younger individuals (-2.50 kg/m²; p = 0.03; interaction between rs7754794 and age: p-value = 0.08). This study provides new insights on the possible influence of MCHR2 and/or MCHR2-AS1 on obesity in psychiatric patients and on the pathophysiology of atypical depression.

Effect of short and long-term treatment with antipsychotics on orexigenic/anorexigenic neuropeptides expression in the rat hypothalamus

Among numerous side effects of antipsychotic drugs (neuroleptics), one of the leading problems is a significant weight gain caused by disturbances in energy homeostasis. The hypothalamus is considered an important target for neuroleptics and contains some neuronal circuits responsible for food intake regulation, so we decided to study which hypothalamic signaling pathways connected with energy balance control are modified by antipsychotic drugs of different generations. We created an expression profile of different neuropeptides after single-dose and chronic neuroleptic administration. Experiments were carried out on adult male Sprague-Dawley rats injected intraperitoneally for 1 day or for 28 days by three neuroleptics: olanzapine, chlorpromazine and haloperidol. Hypothalami were isolated in order to perform PCR reactions and also whole brains were sliced for immunohistochemical analysis. We assessed the expression of orexigenic/anorexigenic neuropeptides and their receptors--neuropeptide Y (NPY), NPY receptor type 1 (Y1R), preproorexin (PPOX), orexin A, orexin receptor type 1 (OX1R) and 2 (OX2R), nucleobindin 2 (NUCB2), nesfatin-1, proopiomelanocortin (POMC), alpha-melanotropin (α-MSH) and melanocortin receptor type 4 (MC4R)--both on the mRNA and protein levels. We have shown that antipsychotics of different generations administered chronically have the ability to upregulate PPOX, orexin A and Y1R expression with little or no effect on orexigenic receptors (OX1R, OX2R) and NPY. Interestingly, antipsychotics also increased the level of some anorexigenic factors (POMC, α-MSH and MC4R), but at the same time strongly downregulated NUCB2 and nesfatin-1 signaling--a newly discovered neuropeptide known as a food-intake inhibiting factor. Our results may contribute to a better understanding of mechanisms responsible for antipsychotics' side effects. They also underline the complex nature of interactions between classical monoamine receptors and hypothalamic peptidergic pathways, which has potential clinical applications.

Growth Hormone Secretagogue Receptor Dimers: A New Pharmacological Target

The growth hormone secretagogue receptor (GHSR1a), the target of the ghrelin peptide, is widely distributed throughout the brain, and, while studies have often reported very low or absent levels of central ghrelin, it is now known that GHSR1a, even in the absence of a natural ligand, has physiological roles. Not only do these roles originate from the receptor's constitutive activity, but recent data indicate that GHSR1a dimerizes with a wide array of other receptors. These include the dopamine 1 receptor (D1R), the dopamine 2 receptor (D2R), the melanocortin-3 receptor (MC3R), the serotonin 2C receptor (5-HT2C), and possibly the cannabinoid type 1 receptor (CB1). Within these dimers, signaling of the protomers involved are modified through facilitation, inhibition, and even modification of signaling pathways resulting in physiological consequences not seen in the absence of these dimers. While in some cases the ghrelin peptide is not required for these modifications to occur, in others, the presence is necessary for these changes to take effect. These heterodimers demonstrate the broad array of roles and complexity of the ghrelin system. By better understanding how these dimers work, it is hoped that improved treatments for a variety of disorders, including Parkinson's disease, schizophrenia, addiction, obesity, diabetes, and more, can be devised. In this review, we examine the current state of knowledge surrounding GHSR heterodimers, and how we can apply this knowledge to various pharmacological treatments.

Differential effects of olanzapine and clozapine on plasma levels of adipocytokines and total ghrelin

Second-generation antipsychotics (SGAs) have been associated with an increased liability for weight gain and metabolic side effects. Among SGAs, clozapine and olanzapine had great liability to induce weight gain and metabolic adverse reactions. Leptin, adiponectin, and total ghrelin play important roles in energy homeostasis and are suggested to be biomarkers of metabolic disturbances. The purpose of the present study was to investigate the differential effects of antipsychotics (olanzapine and clozapine) on the levels of adipocytokines (leptin and adiponectin) and total ghrelin. Three hundred and thirty-three patients with schizophrenia under clozapine or olanzapine monotherapy were recruited. Control participants were recruited from a healthy community population based on a health investigation (N=119). Fasting blood samples for glucose, cholesterol, triglycerides, leptin, adiponectin, and total ghrelin were analyzed. There were significant differences in the levels of cholesterol, triglycerides, and glucose between these three groups. Post hoc comparisons showed that the olanzapine group had the highest levels of cholesterol and triglycerides. The levels of leptin, adiponectin, and total ghrelin were also significantly different between the three groups after controlling age and body mass index (BMI). Post hoc comparisons showed that the olanzapine group had the lowest levels of adiponectin and total ghrelin. The present study found that the uses of olanzapine and clozapine were associated with changes in adipocytokines and total ghrelin, even after adjusting potential confounding factors. Olanzapine had greater influences on adiponectin and total ghrelin than clozapine. The changes in adipocytokines and total ghrelin were a direct effect of antipsychotics on hormonal pathways of energy homeostasis, rather than the result of weight gain.

Ghrelin in psychiatric disorders - A review

Ghrelin is a 28-amino-acid peptide hormone, first described in 1999 and broadly expressed in the organism. As the only known orexigenic hormone secreted in the periphery, it increases hunger and appetite, promoting food intake. Ghrelin has also been shown to be involved in various physiological processes being regulated in the central nervous system such as sleep, mood, memory and reward. Accordingly, it has been implicated in a series of psychiatric disorders, making it subject of increasing investigation, with knowledge rapidly accumulating. This review aims at providing a concise yet comprehensive overview of the role of ghrelin in psychiatric disorders. Ghrelin was consistently shown to exert neuroprotective and memory-enhancing effects and alleviated psychopathology in animal models of dementia. Few human studies show a disruption of the ghrelin system in dementia. It was also shown to play a crucial role in the pathophysiology of addictive disorders, promoting drug reward, enhancing drug seeking behavior and increasing craving in both animals and humans. Ghrelin's exact role in depression and anxiety is still being debated, as it was shown to both promote and alleviate depressive and anxiety-behavior in animal studies, with an overweight of evidence suggesting antidepressant effects. Not surprisingly, the ghrelin system is also implicated in eating disorders, however its exact role remains to be elucidated. Its widespread involvement has made the ghrelin system a promising target for future therapies, with encouraging findings in recent literature.

Leptin and the brain: influences on brain development, cognitive functioning and psychiatric disorders

Receptors of leptin, the prototypical adipokine, are expressed throughout the cortex and several other areas of the brain. Although typically studied for its role in energy intake and expenditure, leptin plays a critical role in many other neurocognitive processes and interacts with various other hormones and neurotransmitters to perform these functions. Here, we review the literature on how leptin influences brain development, neural degradation, Alzheimer's disease, psychiatric disorders, and more complicated cognitive functioning and feeding behaviors. We also discuss modulators of leptin and the leptin receptor as they relate to normal cognitive functioning and may mediate some of the actions of leptin in the brain. Although we are beginning to better understand the critical role leptin plays in normal cognitive functioning, there is much to be discovered.

Serum levels of desacyl ghrelin in patients with schizophrenia on clozapine monotherapy

AIM

Desacyl ghrelin is a hormone that might be a functional inhibitor of ghrelin, a potent hunger-stimulating peptide.

METHODS

We determined fasting serum desacyl ghrelin levels in 24 subjects with schizophrenia on clozapine monotherapy and 24 healthy, age- and sex-matched controls. Biochemical and anthropometric measurements were combined with body composition determined using bioelectric impedance analysis.

RESULTS

There were no differences in desacyl ghrelin levels between patients taking clozapine and the control group (272.09 ± 137.96 vs 259.62 ± 140.91 pg/mL, z = 0.17, P = 0.87). In the clozapine group, there were no differences between men and women for ghrelin levels (246.66 ± 123.17 vs 295.39 ± 151.77 pg/mL, z = -0.98, P = 0.32). In the clozapine group, fasting serum levels of ghrelin negatively correlated with waist-to-hip ratio (WHR) (r = -0.45, P = 0.03) and ionized calcium (r = -0.45, P = 0.03). Levels of ghrelin were lower in patients with WHR above World Health Organization-defined cut-off points (246.84 ± 114.34 [Q1 = 152.18, Q2 = 220.92, Q3 = 327.85] vs 400.30 ± 123.36 [Q1 = 283.73, Q2 = 414.03, Q3 = 485.8] pg/mL, z = 2.52, P = 0.01). In the clozapine group, there were no correlation with age, height, weight, body mass index, abdominal circumference, waist circumference, hip circumference, WHR, blood pressure, total cholesterol, high-density lipoproteins, low-density lipoproteins, triglycerides, uric acid, homocysteine, glucose, insulin, clozapine dose, duration of treatment with antipsychotics, duration of treatment with clozapine, total fat, target fat, basal metabolic rate, target weight, lean weight, body water, homoeostasis model assessment of insulin resistance (HOMA) 1-IR, HOMA2-IR and quantitative insulin sensitivity check index.

CONCLUSION

Based on our results, we cannot conclude that treatment with clozapine affects levels of desacyl ghrelin. Also, in our study population we did not confirm previously described associations between desacyl ghrelin and various metabolic parameters.

Hypothalamic ghrelin signalling mediates olanzapine-induced hyperphagia and weight gain in female rats

Excessive weight gain is a major metabolic side effect of second-generation antipsychotics (SGAs) in the treatment of schizophrenia. Ghrelin is an orexigenic hormone secreted mainly from the stomach, which can induce weight gain and hyperphagia through regulating neuropeptides at the hypothalamus. Accumulating evidence implicates a relationship between ghrelin signalling and SGA-induced hyperphagia and weight gain. We report that olanzapine (a SGA with high weight gain liability) potently and time-dependently up-regulate ghrelin and ghrelin signalling, leading to hyperphagia and weight gain in female Sprague-Dawley rats, an action reversed by i.c.v. injection of a ghrelin receptor (GHS-R1a) antagonist. These findings indicate a crucial role of ghrelin signalling in hyperphagia induced by olanzapine, supporting the notion that GHS-R1a antagonist may be useful for pharmacological treatment of SGA-induced weight gain resulted from hyperphagia.

Obesity and Serious Mental Ill Health: A Critical Review of the Literature

Individuals who experience serious mental ill health such as schizophrenia are more likely to be overweight or obese than others in the general population. This high prevalence of obesity and other associated metabolic disturbances, such as type 2 diabetes and cardiovascular disease, contribute to a reduced life expectancy of up to 25 years. Several reasons have been proposed for high levels of obesity including a shared biological vulnerability between serious mental ill health and abnormal metabolic processes, potentially compounded by unhealthy lifestyles. However, emerging evidence suggests that the most significant cause of weight gain is the metabolic side effects of antipsychotic medication, usual treatment for people with serious mental ill health. In this paper we review the prevalence of obesity in people with serious mental ill health, explore the contribution that antipsychotic medication may make to weight gain and discuss the implications of this data for future research and the practice of mental health and other professionals.

Ghrelin-Derived Peptides: A Link between Appetite/Reward, GH Axis, and Psychiatric Disorders?

Psychiatric disorders are often associated with metabolic and hormonal alterations, including obesity, diabetes, metabolic syndrome as well as modifications in several biological rhythms including appetite, stress, sleep-wake cycles, and secretion of their corresponding endocrine regulators. Among the gastrointestinal hormones that regulate appetite and adapt the metabolism in response to nutritional, hedonic, and emotional dysfunctions, at the interface between endocrine, metabolic, and psychiatric disorders, ghrelin plays a unique role as the only one increasing appetite. The secretion of ghrelin is altered in several psychiatric disorders (anorexia, schizophrenia) as well as in metabolic disorders (obesity) and in animal models in response to emotional triggers (psychological stress …) but the relationship between these modifications and the physiopathology of psychiatric disorders remains unclear. Recently, a large literature showed that this key metabolic/endocrine regulator is involved in stress and reward-oriented behaviors and regulates anxiety and mood. In addition, preproghrelin is a complex prohormone but the roles of the other ghrelin-derived peptides, thought to act as functional ghrelin antagonists, are largely unknown. Altered ghrelin secretion and/or signaling in psychiatric diseases are thought to participate in altered appetite, hedonic response and reward. Whether this can contribute to the mechanism responsible for the development of the disease or can help to minimize some symptoms associated with these psychiatric disorders is discussed in the present review. We will thus describe (1) the biological actions of ghrelin and ghrelin-derived peptides on food and drugs reward, anxiety and depression, and the physiological consequences of ghrelin invalidation on these parameters, (2) how ghrelin and ghrelin-derived peptides are regulated in animal models of psychiatric diseases and in human psychiatric disorders in relation with the GH axis.

In vivo pharmacological evaluations of novel olanzapine analogues in rats: a potential new avenue for the treatment of schizophrenia

Olanzapine (Olz) is one of the most effective antipsychotic drugs commonly used for treating schizophrenia. Unfortunately, Olz administration is associated with severe weight gain and metabolic disturbances. Both patients and clinicians are highly interested in the development of new antipsychotics which are as effective as atypical antipsychotics but which have a lower propensity to induce metabolic side effects. In the present study, we examined two new derivatives of Olz; OlzEt (2-ethyl-4-(4'-methylpiperazin-1'-yl)-10Hbenzo[b]thieno[2,3-e][1,4]diazepine), and OlzHomo (2-ethyl-4-(4'-methyl-1',4'-diazepan-1'-yl)-10H-benzo[b]thieno[2,3-e] [1,4]diazepine), for their tendency to induce weight gain in rats. Weight gain and metabolic changes were measured in female Sprague Dawley rats. Animals were treated orally with Olz, OlzEt, OlzHomo (3 or 6 mg/kg/day), or vehicle (n = 8), three times daily at eight-hour intervals for 5 weeks. Furthermore, a phencyclidine (PCP)-treated rat model was used to examine the prevention of PCP-induced hyperlocomotor activity relevant for schizophrenia therapy. Male Sprague Dawley rats were pre-treated with a single dose (3 mg/kg/day) of Olz, OlzEt, OlzHomo, or vehicle (n = 12), for 2 weeks. Locomotor activity was recorded following a subcutaneous injection with either saline or PCP (10 mg/kg). Olz was found to induce weight gain, hyperphagia, visceral fat accumulation, and metabolic changes associated with reduced histamatergic H1 receptor density in the hypothalamus of treated rats. In contrast, OlzEt and OlzHomo presented promising antipsychotic effects, which did not induce weight gain or fat deposition in the treated animals. Behavioural analysis showed OlzEt to attenuate PCP-induced hyperactivity to a level similar to that of Olz; however, OlzHomo showed a lower propensity to inhibit these stereotyped behaviours. Our data suggest that the therapeutic effectiveness of OlzHomo may be delivered at a higher dose than that of Olz and OlzEt. Overall, OlzEt and OlzHomo may offer a better pharmacological profile than Olz for treating patients with schizophrenia. Clinical trials are needed to test this hypothesis.

The role of ghrelin signalling in second-generation antipsychotic-induced weight gain

Based on clinical and animal studies, this review suggests a tri-phasic effect of second-generation antipsychotics (SGAs) on circulating ghrelin levels: an initial increase exerted by the acute effect of SGAs; followed by a secondary decrease possibly due to the negative feedback from the SGA-induced body weight gain or hyperphagia; and a final re-increase to reach the new equilibrium. Moreover, the results can also vary depending on individual SGAs, other hormonal states, dietary choices, and other confounding factors including medical history, co-treatments, age, gender, and ghrelin measurement techniques. Interestingly, rats treated with olanzapine, an SGA with high weight gain liabilities, are associated with increased hypothalamic ghrelin receptor (GHS-R1a) levels. In addition, expressions of downstream ghrelin signalling parameters at the hypothalamus, including neuropeptide Y (NPY)/agouti-related peptide (AgRP) and proopiomelanocortin (POMC) are also altered under SGA treatments. Thus, understanding the role of ghrelin signalling in antipsychotic drug-induced weight gain should offer potential novel pharmacological targets for tackling the obesity side-effect of SGAs and its associated metabolic syndrome.

The relationships among psychiatric medications, eating behaviors, and weight

To help address gaps in information about the links that exist between psychiatric medications and weight changes, an investigation of relationships among select psychotropic agents (i.e., mood stabilizers, antidepressants, and second-generation antipsychotics {SGAs}), eating behaviors, and weight was conducted. Data from a cross-sectional study of food habits in 97 individuals with mood disorders was used. Variables measured included use of psychotropic agents, measures of cognitive dietary restraint and disinhibition from the Three Factor Eating Behavior Questionnaire (TFEQ), psychiatric functioning, reported weight gain and measured BMI. The TFEQ measures were compared to population norms. Bivariate and multivariate analyses examined the relationships among the psychotropic agents, eating behaviors, and weight. Indicators of cognitive dietary restraint and disinhibition were higher than population norms (p's<0.05 to 0.0001). Depression was associated with restraint (rho=0.21, p<0.05). BMI was associated with disinhibition (p<0.05); antidepressant use appeared to moderate weight for those taking SGAs and mood stabilizers (p<0.05). Exploration of the interacting mechanisms of psychotropic agents and attention to eating attitudes and behaviors of individuals taking psychiatric medications might lessen pharmaceutical-induced weight gain. Prospective research on large samples that can make comparisons to those who are untreated is needed.

The role of leptin in antipsychotic-induced weight gain: genetic and non-genetic factors

Schizophrenia is a chronic and disabling mental illness affecting millions of people worldwide. A greater proportion of people with schizophrenia tends to be overweight. Antipsychotic medications have been considered the primary risk factor for obesity in schizophrenia, although the mechanisms by which they increase weight and produce metabolic disturbances are unclear. Several lines of research indicate that leptin could be a good candidate involved in pathways linking antipsychotic treatment and weight gain. Leptin is a circulating hormone released by adipocytes in response to increased fat deposition to regulate body weight, acting through receptors in the hypothalamus. In this work, we reviewed preclinical, clinical, and genetic data in order to infer the potential role played by leptin in antipsychotic-induced weight gain considering two main hypotheses: (1) leptin is an epiphenomenon of weight gain; (2) leptin is a consequence of antipsychotic-induced "leptin-resistance status," causing weight gain.

Atypical antipsychotic-induced weight gain: insights into mechanisms of action

Prescriptions for second-generation antipsychotics (SGAs) have surpassed those for first-generation agents in the treatment of schizophrenia and bipolar disorder. While SGAs have the benefit of a much reduced risk of causing movement disorders, they have been associated with weight gain and metabolic effects. These adverse reactions are not uncommon, and threaten to have a significant impact on the patient's health over the long-term treatment that the patient requires. Currently, the aetiology of these effects is not known. This article reviews the data exploring the weight gain phenomenon. The literature was reviewed from searches of PubMed and the references of major articles in the field. The SGAs present a heterogeneous risk for weight gain. In addition, different individuals receiving the same drug can exhibit substantially different weight changes. This pattern suggests that a group of factors are associated with the weight gain phenomenon rather than a single mechanism. Coupled with the genetic profile that the patient brings to the treatment, the risk for SGA-induced weight gain will be different for different drugs and different individuals. Targets for exploration of the weight gain phenomenon include receptor interactions involving serotonin, histamine, dopamine, adrenergic, cannabinoid and muscarinic receptors. The association of SGA-induced weight gain and the role of orexigenic and anorexigenic peptides are reviewed. Also, a brief discussion of genetic factors associated with SGA-induced weight gain is presented, including that of the serotonin 5-HT(2C) receptor gene (HTR2C) and the cannabinoid 1 receptor gene (CNR1). The most promising data associated with SGA-induced weight gain include investigations of the histamine H(1), 5-HT(2A), 5-HT(2C), muscarinic M(3) and adrenergic receptors. In addition, work in the genetic area promises to result in a better understanding of the variation in risk associated with different individuals.

Association of serum levels of leptin, ghrelin, and adiponectin in schizophrenic patients and healthy controls

BACKGROUND

Leptin, ghrelin, and adiponectin play important roles in the regulation of body weight, food intake, and energy homeostasis, and have been suggested to be important biomarkers of metabolic syndrome. In this study, we tried to simultaneously investigate the serum levels of leptin, ghrelin, and adiponectin in schizophrenic patients and healthy controls.

METHODS

During a period of 2 years, we recruited 37 schizophrenic patients and 65 healthy controls. The levels of metabolic syndrome-related biomarkers including serum adiponectin, leptin, and ghrelin were measured with an enzyme-linked immunosorbent assay.

RESULTS

On applying analysis of covariance (ANCOVA) with age and body mass index adjustments, the leptin levels of schizophrenic patients (P = 0.038) were found to be higher than those of healthy controls. However, there were no significant differences in the serum levels of ghrelin or adiponectin between these two groups.

CONCLUSION

These results showed that serum leptin levels might be more sensitive than ghrelin or adiponectin levels between schizophrenic patients and healthy controls. However, studies with a large sample size are needed to confirm these results.

Effect of Rikkunshi-to on appetite loss found in elderly dementia patients: a preliminary study

BACKGROUND

Functional gastrointestinal symptoms are frequently found in elderly dementia patients. In such a case, we attempt treatment by the administration of antidepressants or second-generation antipsychotics. However, these medications have a risk of side-effects. In the present study, we carried out oral administration of Rikkunshi-to to elderly dementia patients with appetite loss, and examined its effects on food intake.

METHODS

Six elderly dementia patients were recruited from inpatients. They showed appetite loss, but no organic abnormalities of the gastrointestinal organs. These patients were given Rikkunshi-to, at 7.5 g per day, t.i.d. for 4 weeks. We examined the food intake, weight, total protein, albumin and potassium in plasma before administration and for 4 weeks after administration. In statistical analyses, the percentage of food consumed for 4 weeks was analyzed by anova. We also examined the side-effects of Rikkunshi-to.

RESULTS

In patient 3, we stopped investigation after 3 weeks because of the development of cholecystitis. The values of 4 weeks in patient 3 were calculated as the mean values of 4 weeks in the other five patients. anova and Tukey's multiple comparison showed a marginally significant difference in weight between before Rikkunshi-to was given and 4 weeks after. In change of food intake, there were no significant differences between before Rikkunshi-to was given and 1 day after, 1 day and 2 days after, 2 days and 3 days after, 3 days and 1 week after, and 1 week and 2 weeks after; however, there were significant increases in food intake between other times. With regard to the side-effects, mild lower limb oedema appeared in the two patients.

CONCLUSION

In the present study, we showed the effect of Rikkunshi-to in improving appetite loss in elderly dementia patients. The present study suggests that Rikkunshi-to might be useful in improving functional appetite loss in elderly dementia patients, because there are no serious side-effects.

Olanzapine treatment and metabolic dysfunction: a dose response study in female Sprague Dawley rats

Second generation antipsychotics are commonly prescribed for the treatment of schizophrenia, however some can induce metabolic dysfunction side-effects such as weight gain, obesity and diabetes. Clinical reports suggest olanzapine alters satiety signals, although findings appear conflicting. Previous animal model studies have utilised a range of olanzapine dosages, however the dosage that better mimics the human scenario of olanzapine-induced weight gain is unclear. Female Sprague-Dawley rats were treated orally, three times daily with olanzapine (0.25mg/kg, 0.5mg/kg, 1.0mg/kg, 2.0mg/kg), self-administered in a sweet cookie dough pellet at eight-hourly intervals) or vehicle (n=12/group) for 14-days. Olanzapine orally self-administered in multiple doses (eight-hourly intervals) may circumvent a drop in plasma drug concentration and ensure the maintenance of a consistently high olanzapine level in the rat. Olanzapine increased body weight (0.5mg/kg, 1.0mg/kg, 2.0mg/kg), food intake (2.0mg/kg) and feeding efficiency (0.5-2.0mg/kg), with no effect on water intake. Subcutaneous inguinal (1.0mg/kg, 2.0mg/kg) and intra-abdominal perirenal fat were increased (2.0mg/kg), but not interscapula brown adipose tissue. Olanzapine increased circulating ghrelin and cholecystokinin, but had no effect on peptide YY((3-36)). Olanzapine decreased insulin (0.25-2.0mg/kg) and locomotor activity in the open field arena (0.5-2.0mg/kg). A low dosage of 0.25mg/kg olanzapine had no effect on most parameters measured. Olanzapine-induced weight gain is associated with hyperphagia, enhanced feeding efficiency and adiposity, decreased locomotor activity and altered satiety signaling. The animal model used in the present study of self-administered oral olanzapine treatment (t.i.d.) at a dosage range of 0.5-2.0mg/kg (but not 0.25mg/kg) mimics aspects of the clinic.

Plasma orexin A, ghrelin, cholecystokinin, visfatin, leptin and agouti-related protein levels during 6-week olanzapine treatment in first-episode male patients with psychosis

The objective of the study was to investigate the change of body mass index (BMI), waist circumference, lipid profile, leptin, ghrelin, orexin, visfatin, agouti-related protein, and cholecystokinin levels during 6 weeks of olanzapine treatment in newly diagnosed first-episode drug naive, young adult, nonobese male patients with psychosis. Twenty male participants who were all first-episode drug naive psychotic patients without prominent affective signs and symptoms and 22 healthy male controls of similar age were included. BMI, waist circumference, fasting glucose, and lipid profiles were measured, and Positive and Negative Syndrome Scale and Brief Psychiatric Rating Scale scores were obtained at baseline, during the second and sixth week of treatment, and the aforementioned neuropeptide levels were measured at baseline and during the sixth week of treatment. Treatment was associated with significant increases in BMI, waist circumference, serum triglyceride, and low-density lipoprotein levels. BMI levels increased more than 7% in over 75% of the patients. Leptin increased, and ghrelin and orexin decreased significantly with olanzapine treatment, whereas cholecystokinin, visfatin, and agouti-related protein levels did not change significantly. In conclusion, consistent with previous studies, we found increased BMI, leptin and lipids during olanzapine treatment. Association of neuropeptide level changes with symptom improvement might be mediated by the dopaminergic and serotonergic systems.

Risperidone associated weight, leptin, and anthropometric changes in children and adolescents with psychotic disorders in early treatment

OBJECTIVE

To document prospective weight and anthropometric changes in children and adolescents during the first 12 weeks of treatment with risperidone and evaluate metabolic outcomes including plasma leptin levels.

METHOD

Eight patients with psychotic disorders (ages 11-17) who had started risperidone (mean: 1.80 mg/day; sd = 1.04) in the prior 4 weeks participated in this observational study. Fasting morning blood samples were obtained at baseline and week 8 to assess glucose, leptin, cortisol, insulin, and triglycerides. Measures of body mass index (BMI), weight, waist and hip circumference, blood pressure, and heart rate were obtained weekly.

RESULTS

Participants increased in mean weight (4.16 kg; sd = 4.36; p = 0.03) and BMI (1.47 kg/m(2); sd = 1.53; p = 0.03) with five out of eight gaining at least 7% of baseline body weight. They had a 4.03 cm (sd = 3.82; p = 0.02) increase in waist circumference and a 5.17 cm (sd = 3.68; p = 0.01) increase in hip circumference. Leptin trended higher, but did not reach statistical significance. There were no significant changes in glucose, insulin, cortisol, blood pressure, or heart rate.

CONCLUSION

Subjects experienced significant increases in weight, BMI, hip and waist circumference during the first 3 months of treatment. Better powered research with more advanced anthropometric assessment is warranted to further elucidate mechanisms of antipsychotic associated weight gain in youth.

Weight gain related to treatment with atypical antipsychotics is due to activation of PKC-β

Atypical antipsychotics (APDs) are currently used in clinical practice for a variety of mental disorders such as schizophrenia, bipolar disorder and severe behavioral disturbances. A well-known disadvantage of using these compounds is a propensity for weight gain, resulting frequently in obesity. The mechanisms underlying pharmacologically induced weight gain are still controversial. The objective of this study was to evaluate in vitro the effects of different APDs on adipogenic events in cultured human pre-adipocytes and in rat muscle-derived stem cells (MDSCs), aiming to identify a common intracellular event contributable to these drugs. Culture behavior was evaluated in terms of cell proliferation, lipid accumulation, gene expression and morphological features. Results indicate that APDs influence adipogenic events through changes in the differentiation and proliferation of pre-adipocytes and MDSCs that are brought on by protein kinase C-β (PKC-β) activation. These data identify a signaling route that could be a potential target of pharmacological approaches for preventing the weight gain associated with APD treatment.

Contributing factors to weight gain during long-term treatment with second-generation antipsychotics. A systematic appraisal and clinical implications

The increased rates of both overweight and obesity reported in severely mentally-ill patients are prevalently due to the use of second-generation antipsychotics (SGAs). Hence, the main purpose of this article is to analyze systematically potential patient- and drug-related factors which may increase the risk of weight gain during long-term treatment with such medications. Literature information published in English since 1966 and last updated on 17 January 2009 was identified through different databases and using various combinations of search terms. Searches provided 242 articles, whereas 6 additional references were identified manually. Peer-reviewed articles focusing on the risk of weight gain during SGA-chronic treatment (at least 52 weeks, N = 81) were acquired. Data were extracted from the 39 peer-reviewed articles which investigated factors potentially associated with an increased risk of this event. Evidence-based information suggests that a number of factors, either patient- (age, baseline BMI/bodyweight, recent onset of psychotic episodes, need of concomitant psychotropic medications) or drug-specific (relative receptorial affinity, timing of weight changes plateau, daily dose, iatrogenic concomitant changes in biochemical metabolic parameters) may contribute to increase either rates and/or magnitude of this effect during long-term treatments with specific SGAs. All contributors and their relationship with specific drugs should be taken into consideration when designing a long-term therapy with SGAs. Among the best studied agents (clozapine, olanzapine, and risperidone) of this class, the latter seems to be the most susceptible drug to the amplifying effects of both patient- and drug-related factors on the risk of inducing weight changes during chronic treatments.

Antipsychotic-induced body weight gain: predictors and a systematic categorization of the long-term weight course

OBJECTIVE

To explore the impact of premorbid and baseline body mass indices (BMIs) as well as BMI of patient's parents and associated variables on the prediction of antipsychotic-induced body weight gain.

METHODS

Retrospective/cross-sectional data of 65 patients receiving clozapine, olanzapine and/or risperidone were assessed according to a systematic categorization of the long-term (7.3+/-9.2 years) weight course and evaluated using descriptive, explorative correlation and regression analyses.

RESULTS

Increased values of parents' BMI (p=0.041) and patients' BMI at premorbid stage (p=0.039) and prior to first antipsychotic treatment (p=0.032) as well as female gender (p=0.012), younger age (p=0.005) and non-smoking (p=0.047) have the most predictive value on body weight gain under antipsychotic treatment including pre-treatment with typical antipsychotics. Weight gain under atypical antipsychotics (pre-treatment excluded) is predicted by an increased premorbid BMI (p=0.019). Conversely, a low BMI prior to first antipsychotic treatment predicts a higher acceleration of BMI change (p=0.008) in vulnerable individuals, but not total BMI change itself. Furthermore, a diagnosis of a schizophrenia spectrum disorder showed a trend towards the prediction of an increased atypical DeltaBMI (p=0.067), possibly due to a longer treatment duration with atypical antipsychotics (p<0.001).

DISCUSSION

The study indicates increased parents' BMI and patients' premorbid BMI, female gender, younger age and - as a trend - the diagnosis of a schizophrenia spectrum disorder to be predictors for antipsychotic-induced body weight gain involving atypical antipsychotics. Data contribute to the assumption of a strong impact of predispositional factors on weight gain, besides treatment-related factors.