The Effect of Chronic Treatment with Lurasidone on Rat Liver Cytochrome P450 Expression and Activity in the Chronic Mild Stress Model of Depression

The Novel Atypical Antipsychotic Lurasidone Affects Cytochrome P450 Expression in the Liver and Peripheral Blood Lymphocytes

Lurasidone is a novel atypical antipsychotic drug acting on dopaminergic, serotonergic and noradrenergic receptors; it is applied for the long-term treatment of schizophrenia and depression in patients with bipolar disorders. We aimed at performing a comparative study on the influence of chronic treatment with lurasidone on the expression of cytochrome P450 enzymes in the liver and in peripheral blood lymphocytes, and to evaluate the relationship between changes in the expression of CYP enzymes in the two experimental models. The obtained results show a fairly similar expression pattern of the main CYP enzymes in the rat livers and lymphocytes, and they indicate that in the liver, lurasidone exerts an inhibitory effect on the activity, protein and mRNA levels of CYP2B1/2 (not CYP2B2 mRNA), CYP2C11 and CYP2E1, while in the case of CYP3A1 and CYP3A2, it causes enzyme induction. At the same time, lurasidone decreases the expression of CYP2B, CYP2C11 (CYP2C11 protein only) and CYP2E1 but increases that of CYP3A2 (not CYP3A1) in lymphocyte cells. In conclusion, chronic treatment with lurasidone simultaneously and in the same way influences the expression and activity of CYP2B, CYP2C11, CYP2E1 and CYP3A2 in the liver and peripheral blood lymphocytes of rats. Thus, the lymphocyte cytochrome P450 profile may be utilized as an indicator of the hepatic cytochrome P450 profile in further clinical studies with lurasidone, and lymphocytes may serve as easily available surrogates for examining the impact of new drugs and chronic in vivo treatments on CYP enzyme expression, as well as to estimate drug-drug interactions and toxicity risk.

Systems biology approaches to identify potential targets and inhibitors of the intestinal microbiota to treat depression

Depression is a common mental disease, with some patients exhibiting ideas and behaviors such as self-harm and suicide. The drugs currently used to treat depression have not achieved good results. It has been reported that metabolites produced by intestinal microbiota affect the development of depression. In this study, core targets and core compounds were screened by specific algorithms in the database, and three-dimensional structures of these compounds and proteins were simulated by molecular docking and molecular dynamics software to further study the influence of intestinal microbiota metabolites on the pathogenesis of depression. By analyzing the RMSD gyration radius and RMSF, it was finally determined that NR1H4 had the best binding effect with genistein. Finally, according to Lipinski's five rules, equol, genistein, quercetin and glycocholic acid were identified as effective drugs for the treatment of depression. In conclusion, the intestinal microbiota can affect the development of depression through the metabolites equol, genistein and quercetin, which act on the critical targets of DPP4, CYP3A4, EP300, MGAM and NR1H4.

The Influence of Long-Term Treatment with Asenapine on Liver Cytochrome P450 Expression and Activity in the Rat. The Involvement of Different Mechanisms

Therapy of schizophrenia requires long-term treatment with a relevant antipsychotic drug to achieve a therapeutic effect. The aim of the present study was to investigate the influence of prolonged treatment with the atypical neuroleptic asenapine on the expression and activity of rat cytochrome P450 (CYP) in the liver. The experiment was carried out on male Wistar rats. Asenapine (0.3 mg/kg s.c.) was administered for two weeks. The levels of CYP mRNA protein and activity were determined in the liver and hormone concentrations were measured in the pituitary gland and blood serum. Asenapine significantly decreased the activity of CYP1A (caffeine 8-hydroxylation and 3-N-demethylation), CYP2B, CYP2C11 and CYP3A (testosterone hydroxylation at positions 16β; 2α and 16α; 2β and 6β, respectively). The neuroleptic did not affect the activity of CYP2A (testosterone 7α-hydroxylation), CYP2C6 (warfarin 7-hydroxylation) and CYP2E1 (chlorzoxazone 6-hydroxylation). The mRNA and protein levels of CYP1A2, CYP2B1, CYP2C11 and CYP3A1 were decreased, while those of CYP2B2 and CYP3A2 were not changed. Simultaneously, pituitary level of growth hormone-releasing hormone and serum concentrations of growth hormone and corticosterone were reduced, while that of triiodothyronine was enhanced. In conclusion, chronic treatment with asenapine down-regulates liver cytochrome P450 enzymes, which involves neuroendocrine mechanisms. Thus, chronic asenapine treatment may slow the metabolism of CYP1A, CYP2B, CYP2C11 and CYP3A substrates (steroids and drugs). Since asenapine is metabolized by CYP1A and CYP3A, the neuroleptic may inhibit its own metabolism, therefore, the plasma concentration of asenapine in patients after prolonged treatment may be higher than expected based on a single dose.

The effects of agomelatine and imipramine on liver cytochrome P450 during chronic mild stress (CMS) in the rat

BACKGROUND

The aim of our research was to determine the effects of chronic treatment with the atypical antidepressant agomelatine on the expression and activity of liver cytochrome P450 (CYP) in the chronic mild stress (CMS) model of depression, and to compare the results with those obtained for the first-generation antidepressant imipramine.

METHODS

Male Wistar rats were subjected to CMS for 7 weeks. Imipramine (10 mg/kg ip/day) or agomelatine (40 mg/kg ip/day) was administered to nonstressed or stressed animals for 5 weeks (weeks 3-7 of CMS). The levels of cytochrome P450 mRNA, protein and activity were measured in the liver.

RESULTS

Agomelatine and imipramine produced different broad-spectrum effects on cytochrome P450. Like imipramine, agomelatine increased the expression/activity of CYP2B and CYP2C6, and decreased the CYP2D activity. Unlike imipramine, agomelatine raised the expression/activity of CYP1A, CYP2A and reduced that of CYP2C11 and CYP3A. CMS modified the effects of antidepressants at transcriptional/posttranscriptional level; however, the enzyme activity in stressed rats remained similar to that in nonstressed animals. CMS alone decreased the CYP2B1 mRNA level and increased that of CYP2C11.

CONCLUSION

We conclude the following: (1) the effects of agomelatine and imipramine on cytochrome P450 are different and involve both central and peripheral regulatory mechanisms, which implicates the possibility of drug-drug interactions; (2) CMS influences the effects of antidepressants on cytochrome P450 expression, but does not change appreciably their effects on the enzyme activity. This suggests that the rate of antidepressant drug metabolism under CMS is similar to that under normal conditions.

Ablation of olfactory bulb glutamatergic neurons induces depressive-like behaviors and sleep disturbances in mice

RATIONALE

Major depression is a serious, but common, psychological disorder, which consists of a long-lasting depressive mood, feelings of helplessness, anhedonia, and sleep disturbances. It has been reported that rats with bilateral olfactory bulbectomies (OBXs) exhibit depressive-like behaviors which indicates that the olfactory bulb (OB) plays an important role in the formation of depression. However, which type of OB neurons plays an important role in the formation of depression remains unclear.

OBJECTIVE

To determine the role of OB neuronal types in depression and related sleep-wake dysfunction.

METHODS

Firstly, we established and evaluated a conventional physical bilateral OBX depression model. Secondly, we used chemical methods to ablate OB neurons, while maintaining the original shape, and evaluated depressive-like behaviors. Thirdly, we utilized AAV-flex-taCasp3-TEVp and transgenetic mice to specifically ablate the OB GABAergic or glutamatergic neurons, then evaluated depressive-like behaviors.

RESULTS

Compared with measured parameters in sham mice, mice with OBXs or ibotenic acid-induced OB lesions exhibited depressive-like behaviors and sleep disturbances, as demonstrated by results of depressive-like behavior tests and sleep recordings. Selective lesioning of OB glutamatergic neurons, but not GABAergic neurons induced depressive-like behaviors and increased rapid eye movement sleep during the light phase of the circadian cycle.

CONCLUSIONS

These results indicate that OB glutamatergic neurons play a key role in olfactory-related depression and sleep disturbance.

Quantitative proteomic analysis of the liver reveals antidepressant potential protein targets of Sinisan in a mouse CUMS model of depression

In traditional Chinese medicine, the role of the liver in depression is highly valued, and liver-relieving drugs, such as Sinisan, are often used to treat depression; however, the mechanism whereby these drugs work remains unclear. The present study aimed to reveal possible antidepressant mechanisms of Sinisan (SNS) by analyzing hepatic proteomics in chronic unpredictable mild stress (CUMS) mice. Using the CUMS mouse model of depression, the antidepressant effects of SNS were assessed by the sucrose preference test (SPT) and forced swimming test (FST). Hepatic differentially expressed proteins (DEPs) after SNS treatment were investigated by tandem mass tag (TMT) based quantitative proteomics analysis. Then, a bioinformatics analysis of DEPs was conducted through hierarchical clustering, Venn analysis, Gene Ontology (GO) annotation enrichment, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. DEP genes were further validated by quantitative real-time polymerase chain reaction (qRT-PCR) analysis and western blotting. Behavioral results demonstrated that SNS significantly increased sucrose intake in SPT and shortened the immobility time in FST in model mice. Eighty-two DEPs were identified, including 37 upregulated and 45 downregulated proteins, between model and SNS groups. Enrichment analysis of GO annotations indicated that SNS primarily maintained cellular iron ion homeostasis by iron ion transportation and regulated expression of some extracellular structural proteins for oxidation-reduction processes. KEGG and Venn analysis showed that mineral absorption, steroid hormone biosynthesis and metabolism might be the principal pathways through which SNS acts on depression. Furthermore, several proteins involved in the biosynthesis and metabolism of steroid hormone pathways were significantly up/downregulated by SNS, including CYP2B19, CYP7B1 (validated by qRT-PCR) and HSD3b5 (validated by qRT-PCR and western blotting). Our results indicate that SNS plays important roles in antidepressant actions by restoring DEPs, resulting in the biosynthesis and metabolism of steroid hormones. The current results provide novel perspectives for revealing potential protein targets of SNS in depression.

Chaihu-Shugan-San Reinforces CYP3A4 Expression via Pregnane X Receptor in Depressive Treatment of Liver-Qi Stagnation Syndrome

Backgrounds. Chaihu-Shugan-San (CSS) is a classic traditional Chinese herbal prescription for treating depression. However, the underlying mechanism of the Chinese syndrome-specific efficacy of CSS is poorly understood. Aim of the Study. From traditional Chinese medicine and pharmacogenetics perspectives, the present study aimed to investigate the antidepressant effects of CSS on a mouse model of Liver-Qi Stagnation (LQS) syndrome and its underlying mechanisms. Methods and Materials. We used two main mouse models of depressive syndromes in the study, including LQS and liver stagnation and spleen deficiency (LSSD) syndrome. Tail suspension and forced swimming tests were used to evaluate the effects of CSS on animal behaviour. The expression level of the CYP450 enzyme from liver microsomes was analysed by western blot (WB) analysis and quantitative real-time polymerase chain reaction (qRT-PCR). More specifically, we analysed the key compounds of CSS that are responsible for CYP450 regulation via bioinformatics. Ultimately, luciferase assays were employed to confirm the prediction in vitro. Results. CSS remarkably reduced the immobile time in LQS rather than in LSSD mice. Although CSS significantly upregulated CYP2C9 in mice with both syndromes, activated translation of CYP3A4 induced by CSS was only observed in the LQS group. Bioinformatics analysis revealed that the unique regulation of CYP3A4 was responsible for the effects of glycyrrhetinic acid (GA) from CSS. Further luciferase assays confirmed the enhancement of CYP3A4 expression via the pregnane X receptor (PXR) pathway in vitro. Conclusions. CSS specifically upregulates the translation of CYP3A4 via the PXR pathway in depressed LQS mice. GA, a bioactive compound that originates from CSS, contributes to this activation. This work provides novel insight into Chinese syndrome-based therapy for depression.

The engagement of brain cytochrome P450 in the metabolism of endogenous neuroactive substrates: a possible role in mental disorders

The current state of knowledge indicates that the cerebral cytochrome P450 (CYP) plays an important role in the endogenous metabolism in the brain. Different CYP isoenzymes mediate metabolism of many endogenous substrates such as monoaminergic neurotransmitters, neurosteroids, cholesterol, vitamins and arachidonic acid. Therefore, these enzymes may affect brain development, susceptibility to mental and neurodegenerative diseases and may contribute to their pathophysiology. In addition, they can modify the therapeutic effects of psychoactive drugs at the place of their target action in the brain, where the drugs can act by affecting the metabolism of endogenous substrates. The article focuses on the role of cerebral CYP isoforms in the metabolism of neurotransmitters, neurosteroids, and cholesterol, and their possible involvement in animal behavior, as well as in stress, depression, schizophrenia, cognitive processes, learning, and memory. CYP-mediated alternative pathways of dopamine and serotonin synthesis may have a significant role in the local production of these neurotransmitters in the brain regions where the disturbances of these neurotransmitter systems are observed in depression and schizophrenia. The local alternative synthesis of neurotransmitters may be of great importance in the brain, since dopamine and serotonin do not pass the blood-brain barrier and cannot be supplied from the periphery. In vitro studies indicate that human CYP2D6 catalyzing dopamine and serotonin synthesis is more efficient in these reactions than the rat CYP2D isoforms. It suggests that these alternative pathways may have much greater significance in the human brain but confirmation of these assumptions requires further studies.

The activity of brain and liver cytochrome P450 2D (CYP2D) is differently affected by antidepressants in the chronic mild stress (CMS) model of depression in the rat

The effect of two second-generation antidepressants escitalopram and venlafaxine on the activity of brain and liver cytochrome P450 2D (CYP2D) involved in the metabolism of psychotropics and neurotransmitters was determined in the chronic mild stress (CMS) model of depression. Escitalopram or venlafaxine (10 mg/kg ip/day each) were administered to control and CMS rats for 5 weeks. The activity of CYP2D was studied by measurement of the rate of bufuralol 1'-hydroxylation in microsomes derived from the liver or different brain structures. The obtained results indicate that CMS and the studied antidepressants had different effects on the CYP2D activity depending on the location of the enzyme. In the brain, CMS produced an increase in the CYP2D activity in the hippocampus. Chronic escitalopram or venlafaxine had no effect on the CYP2D activity in the brain of nonstressed rats, however, the antidepressants increased the enzyme activity in the frontal cortex, hypothalamus and cerebellum of stressed animals. In the liver, CMS did not affect the CYP2D activity, while chronic escitalopram or venlafaxine significantly decreased the CYP2D activity and protein level in nonstressed and stressed rats. We conclude that: 1) CMS stimulates the CYP2D activity in the hippocampus and triggers the stimulatory effect of antidepressants on CYP2D in other brain structures; 2) the local brain metabolism of CYP2D substrates (neurosteroids, neurotransmitters, psychotropics) may be enhanced by CMS and/or antidepressants; 3) in contrast to the brain, the liver metabolism of CYP2D substrates may be slower during long-term treatment with escitalopram or venlafaxine.

Altered cytokine profile under control of the serotonergic system determines the regulation of CYP2C11 and CYP3A isoforms

The aim of this study is to assess a potential mechanism by which the serotonergic system can control the expression and activity of cytochrome (CYP) 2C11 and CYP3A isoforms during liver insufficiency. A rat model of diethylnitrosamine (DEN)-induced liver insufficiency was developed by administering 50 mg/kg of DEN twice a week for 7 weeks. Dysfunction of the serotonergic system was evoked by feeding the rats with a tryptophan-free diet for three weeks. Dysfunction of the serotonergic system during liver insufficiency decreased the level of proinflammatory cytokines (TGF-β and IL-1β) and increased the level of an anti-inflammatory cytokine (IL-4). Simultaneously, activation of the repressive mechanism IL-4/JAK1/STAT6/SOCS1 of the JAK2/STAT5b-mediated signal transduction pathway and the pERK1/2/GR/STAT6 signal transduction pathway resulted in the suppression of the CYP2C11 and CYP3A isoforms. Moreover, dysfunction of the serotonergic system during liver insufficiency equalized the level of testosterone to the basal level, did not change the steady state of the corticosterone level and significantly enhanced the reduced level of growth hormone. An altered cytokine profile under control of the serotonergic system determines the regulation of CYP2C11 and CYP3A isoforms during liver insufficiency through mechanisms based on posttranscriptional and posttranslational processes.