Conformational rearrangements in the second voltage sensor domain switch PIP2- and voltage-gating modes in two-pore channels.

Two-pore channels (TPCs) are activated by phosphatidylinositol bisphosphate (PIP2) binding to domain I and/or by voltage sensing in domain II (DII). Little is known about how these two stimuli are integrated, and how each TPC subtype achieves its unique preference. Here, we show that distinct conformations of DII-S4 in the voltage-sensor domain determine the two gating modes. DII-S4 adopts an intermediate conformation, and forced stabilization in this conformation was found to result in a high PIP2-dependence in primarily voltage-dependent TPC3. In TPC2, which is PIP2-gated and nonvoltage-dependent, a stabilized intermediate conformation does not affect the PIP2-gated currents. These results indicate that the intermediate state represents the PIP2-gating mode, which is distinct from the voltage-gating mode in TPCs. We also found in TPC2 that the tricyclic antidepressant desipramine induces DII-S4-based voltage dependence and that naringenin, a flavonoid, biases the mode preference from PIP2-gating to desipramine-induced voltage gating. Taken together, our study on TPCs revealed an unprecedented mode-switching mechanism involving conformational changes in DII-S4, and its active role in integrating voltage and PIP2 stimuli.

Chronic Desipramine Reverses Deficits in Cell Activity, Norepinephrine Innervation, and Anxiety-Depression Phenotypes in Fluoxetine-Resistant cF1ko Mice.

Selective serotonin (5-HT) reuptake inhibitors are only 30% effective for remission in subjects with major depression, and the best treatments for SSRI-resistant patients remain unclear. To model SSRI resistance, we used cF1ko mice with conditional deletion of the repressor Freud-1/CC2D1A in adult 5-HT neurons. Within weeks, this deletion leads to overexpression of 5-HT1A autoreceptors, reduced serotonergic activity, and fluoxetine-resistant anxiety-depression phenotype. We hypothesized that desipramine (DES), which targets norepinephrine (NE), may be effective in cF1ko mice. The actions of chronic DES treatment on behavior, chronic cellular activation, and NE projections were examined in both sexes of cF1ko and WT mice. In contrast to fluoxetine, chronic DES reversed the behavioral phenotypes in cF1ko mice, while in WT littermates DES slightly increased anxiety and depression-like behaviors. Deficits in FosB+ cell counts were seen in the entorhinal cortex, hippocampal CA2/3 layer, and BLA of cF1ko mice and were reversed by chronic DES treatment, especially in GABAergic neurons. In cF1ko mice, widespread reductions were seen in NE axons, varicosities, and especially 30-60% reductions in NE synaptic and triadic contacts, particularly to inhibitory gephyrin-positive sites. DES treatment also reversed these reductions in NE innervation. These results indicate the dynamic plasticity of the adult noradrenergic system within weeks of altering serotonergic function that can be normalized by DES treatment. Accompanying these changes, DES but not fluoxetine reversed the behavioral alterations in cF1ko mice, suggesting a key role for noradrenergic plasticity in antidepressant response in this model of reduced serotonin activity.

Protective effects of curcumin on desipramine-induced islet ß-cell damage via AKAP150/PKA/PP2B complex.

Tricyclic antidepressants (TCAs) are widely used to treat depression and anxiety-related mood disorders. But evidence shows that TCAs elevate blood glucose levels and inhibit insulin secretion, suggesting that TCAs are a risk factor, particularly for individuals with diabetes. Curcumin is a bioactive molecule from the rhizome of the Curcuma longa plant, which has shown both antidepressant and anti-diabetic activities. In the present study, we investigated the protective effect of curcumin against desipramine-induced apoptosis in ß cells and the underlying molecular mechanisms. In the mouse forced swimming test (FST), we found that lower doses of desipramine (5 and 10 mg/kg) or curcumin (2.5 mg/kg) alone did not affect the immobility time, whereas combined treatment with curcumin (2.5 mg/kg) and desipramine (5, 10 mg/kg) significantly decreased the immobility time. Furthermore, desipramine dose-dependently inhibited insulin secretion and elevated blood glucose levels, whereas the combined treatment normalized insulin secretion and blood glucose levels. In RIN-m5F pancreatic ß-cells, desipramine (10 µM) significantly reduced the cell viability, whereas desipramine combined with curcumin dose-dependently prevented the desipramine-induced impairment in glucose-induced insulin release, most effectively with curcumin (1 and 10 µM). We demonstrated that desipramine treatment promoted the cleavage and activation of Caspase 3 in RIN-m5F cells. Curcumin treatment inhibited desipramine-induced apoptosis, increased mitochondrial membrane potential and Bcl-2/Bax ratio. Desipramine increased the generation of reactive oxygen species, which was reversed by curcumin treatment. Curcumin also inhibited the translocation of forkhead box protein O1 (FOXO1) from the cytoplasm to the nucleus and suppressed the binding of A-kinase anchor protein 150 (AKAP150) to protein phosphatase 2B (PP2B, known as calcineurin) that was induced by desipramine. These results suggest that curcumin protects RIN-m5F pancreatic ß-cells against desipramine-induced apoptosis by inhibiting the phosphoinositide 3-kinase/AKT/FOXO1 pathway and the AKAP150/PKA/PP2B interaction. This study suggests that curcumin may have therapeutic potential as an adjunct to antidepressant treatment.

Structure- and Cation-Dependent Mechanism of Interaction of Tricyclic Antidepressants with NMDA Receptor According to Molecular Modeling Data.

Some tricyclic antidepressants (TCAs), including amitriptyline (ATL), clomipramine (CLO), and desipramine (DES), are known to be effective for management of neuropathic pain. It was previously determined that ATL, CLO, and DES are capable of voltage-dependent blocking of NMDA receptors of glutamate (NMDAR), which play a key role in pathogenesis of neuropathic pain. Despite the similar structure of ATL, CLO, and DES, efficacy of their interaction with NMDAR varies significantly. In the study presented here, we applied molecular modeling methods to investigate the mechanism of binding of ATL, CLO, and DES to NMDAR and to identify structural features of the drugs that determine their inhibitory activity against NMDAR. Molecular docking of the studied TCAs into the NMDAR channel was performed. Conformational behavior of the obtained complexes in the lipid bilayer was simulated by the method of molecular dynamics (MD). A single binding site (upper) for the tertiary amines ATL and CLO and two binding sites (upper and lower) for the secondary amine DES were identified inside the NMDAR channel. The upper and lower binding sites are located along the channel axis at different distances from the extracellular side of the plasma membrane. MD simulation revealed that the position of DES in the lower site is stabilized only in the presence of sodium cation inside the NMDAR channel. DES binds more strongly to NMDAR compared to ATL and CLO due to simultaneous interaction of two hydrogen atoms of its cationic group with the asparagine residues of the ion pore of the receptor. This feature may be responsible for the stronger side effects of DES. It has been hypothesized that ATL binds to NMDAR less efficiently compared to DES and CLO due to its lower conformational mobility. The identified features of the structure- and cation-dependent mechanism of interaction between TCAs and NMDAR will help in the further development of effective and safe analgesic therapy.

Desipramine ameliorates fine particulate matter-induced hepatic insulin resistance by modulating the ceramide metabolism in mice.

Recent research has highlighted a correlation between exposure to ambient fine particulate matter (PM2.5) and the development of systemic insulin resistance (IR) along with an elevated risk of diabetes. Ceramide has emerged as one of the pathogenic mechanisms contributing to IR. The inhibition of acid sphingomyelinase (ASMase) activity by desipramine (DES) has been shown to effectively reduce ceramide levels. In the present study, 24 female C57BL/6 N mice were randomized into one of the four groups: the filtered air exposure (FA) group, the concentrated PM2.5 exposure (PM) group, the concentrated PM2.5 treated with low-dose DES (DL) group, and the concentrated PM2.5 treated with high-dose DES (DH) group. The PM, DL and DH groups were exposed to PM2.5 for an 8-week period within a whole-body exposure system. The study encompassed extensive examinations of glucose homeostasis, liver lipid profile, ceramide pathway, and insulin signaling pathway. Our results demonstrated that PM2.5 exposure caused impaired glucose tolerance, elevated ceramide levels, increased phosphorylation PP2A, reduced Akt phosphorylation, and hindered GLUT2 expression. Remarkably, DES administration mitigated PM2.5-induced IR by effectively lowering ceramide levels. In conclusion, the reduction of ceramide levels by DES may be a promising therapeutic strategy for coping PM2.5-induced IR.

Synergistic Enhancement of Antitumor Effects by Combining Abemaciclib with Desipramine.

Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors, including abemaciclib, have been approved for the treatment of hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced, and metastatic breast cancer. Despite the high therapeutic efficacy of CDK4/6 inhibitors, they are associated with various adverse effects, including potentially fatal interstitial lung disease. Therefore, a combination of CDK4/6 inhibitors with letrozole or fulvestrant has been attempted but has demonstrated limitations in reducing adverse effects, highlighting the need to develop new combination therapies. This study proposes a combination strategy using CDK4/6 inhibitors and tricyclic antidepressants to enhance the therapeutic outcomes of these inhibitors while reducing their side effects. The therapeutic efficacies of abemaciclib and desipramine were tested in different cancer cell lines (H460, MCF7, and HCT-116). The antitumor effects of the combined abemaciclib and desipramine treatment were evaluated in a xenograft colon tumor model. In vitro cell studies have shown the synergistic anticancer effects of combination therapy in the HCT-116 cell line. The combination treatment significantly reduced tumor size compared with control or single treatment without causing apparent toxicity to normal tissues. Although additional in vivo studies are necessary, this study suggests that the combination therapy of abemaciclib and desipramine may represent a novel therapeutic approach for treating solid tumors.

Pharmacological treatments in panic disorder in adults: a network meta-analysis.

BACKGROUND: A panic attack is a discrete period of fear or anxiety that has a rapid onset and reaches a peak within 10 minutes. The main symptoms involve bodily systems, such as racing heart, chest pain, sweating, shaking, dizziness, flushing, churning stomach, faintness and breathlessness. Other recognised panic attack symptoms involve fearful cognitions, such as the fear of collapse, going mad or dying, and derealisation (the sensation that the world is unreal). Panic disorder is common in the general population with a prevalence of 1% to 4%. The treatment of panic disorder includes psychological and pharmacological interventions, including antidepressants and benzodiazepines. OBJECTIVES: To compare, via network meta-analysis, individual drugs (antidepressants and benzodiazepines) or placebo in terms of efficacy and acceptability in the acute treatment of panic disorder, with or without agoraphobia. To rank individual active drugs for panic disorder (antidepressants, benzodiazepines and placebo) according to their effectiveness and acceptability. To rank drug classes for panic disorder (selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), mono-amine oxidase inhibitors (MAOIs) and benzodiazepines (BDZs) and placebo) according to their effectiveness and acceptability. To explore heterogeneity and inconsistency between direct and indirect evidence in a network meta-analysis. SEARCH METHODS: We searched the Cochrane Common Mental Disorders Specialised Register, CENTRAL, CDSR, MEDLINE, Ovid Embase and PsycINFO to 26 May 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of people aged 18 years or older of either sex and any ethnicity with clinically diagnosed panic disorder, with or without agoraphobia. We included trials that compared the effectiveness of antidepressants and benzodiazepines with each other or with a placebo. DATA COLLECTION AND ANALYSIS: Two authors independently screened titles/abstracts and full texts, extracted data and assessed risk of bias. We analysed dichotomous data and continuous data as risk ratios (RRs), mean differences (MD) or standardised mean differences (SMD): response to treatment (i.e. substantial improvement from baseline as defined by the original investigators: dichotomous outcome), total number of dropouts due to any reason (as a proxy measure of treatment acceptability: dichotomous outcome), remission (i.e. satisfactory end state as defined by global judgement of the original investigators: dichotomous outcome), panic symptom scales and global judgement (continuous outcome), frequency of panic attacks (as recorded, for example, by a panic diary; continuous outcome), agoraphobia (dichotomous outcome). We assessed the certainty of evidence using threshold analyses. MAIN RESULTS: Overall, we included 70 trials in this review. Sample sizes ranged between 5 and 445 participants in each arm, and the total sample size per study ranged from 10 to 1168. Thirty-five studies included sample sizes of over 100 participants. There is evidence from 48 RCTs (N = 10,118) that most medications are more effective in the response outcome than placebo. In particular, diazepam, alprazolam, clonazepam, paroxetine, venlafaxine, clomipramine, fluoxetine and adinazolam showed the strongest effect, with diazepam, alprazolam and clonazepam ranking as the most effective. We found heterogeneity in most of the comparisons, but our threshold analyses suggest that this is unlikely to impact the findings of the network meta-analysis. Results from 64 RCTs (N = 12,310) suggest that most medications are associated with either a reduced or similar risk of dropouts to placebo. Alprazolam and diazepam were associated with a lower dropout rate compared to placebo and were ranked as the most tolerated of all the medications examined. Thirty-two RCTs (N = 8569) were included in the remission outcome. Most medications were more effective than placebo, namely desipramine, fluoxetine, clonazepam, diazepam, fluvoxamine, imipramine, venlafaxine and paroxetine, and their effects were clinically meaningful. Amongst these medications, desipramine and alprazolam were ranked highest. Thirty-five RCTs (N = 8826) are included in the continuous outcome reduction in panic scale scores. Brofaromine, clonazepam and reboxetine had the strongest reductions in panic symptoms compared to placebo, but results were based on either one trial or very small trials. Forty-one RCTs (N = 7853) are included in the frequency of panic attack outcome. Only clonazepam and alprazolam showed a strong reduction in the frequency of panic attacks compared to placebo, and were ranked highest. Twenty-six RCTs (N = 7044) provided data for agoraphobia. The strongest reductions in agoraphobia symptoms were found for citalopram, reboxetine, escitalopram, clomipramine and diazepam, compared to placebo. For the pooled intervention classes, we examined the two primary outcomes (response and dropout). The classes of medication were: SSRIs, SNRIs, TCAs, MAOIs and BDZs. For the response outcome, all classes of medications examined were more effective than placebo. TCAs as a class ranked as the most effective, followed by BDZs and MAOIs. SSRIs as a class ranked fifth on average, while SNRIs were ranked lowest. When we compared classes of medication with each other for the response outcome, we found no difference between classes. Comparisons between MAOIs and TCAs and between BDZs and TCAs also suggested no differences between these medications, but the results were imprecise. For the dropout outcome, BDZs were the only class associated with a lower dropout compared to placebo and were ranked first in terms of tolerability. The other classes did not show any difference in dropouts compared to placebo. In terms of ranking, TCAs are on average second to BDZs, followed by SNRIs, then by SSRIs and lastly by MAOIs. BDZs were associated with lower dropout rates compared to SSRIs, SNRIs and TCAs. The quality of the studies comparing antidepressants with placebo was moderate, while the quality of the studies comparing BDZs with placebo and antidepressants was low. AUTHORS' CONCLUSIONS: In terms of efficacy, SSRIs, SNRIs (venlafaxine), TCAs, MAOIs and BDZs may be effective, with little difference between classes. However, it is important to note that the reliability of these findings may be limited due to the overall low quality of the studies, with all having unclear or high risk of bias across multiple domains. Within classes, some differences emerged. For example, amongst the SSRIs paroxetine and fluoxetine seem to have stronger evidence of efficacy than sertraline. Benzodiazepines appear to have a small but significant advantage in terms of tolerability (incidence of dropouts) over other classes.

Polycarbonate-coated magnetic nanoparticles for the extraction of imipramine and its primary metabolite from urine.

This study introduces a reliable and inexpensive magnetic dispersive solid phase extraction to extract imipramine and its primary metabolite (desipramine) from urine samples. To accomplish this aim, Fe3 O4 magnetic nanoparticles were synthesized by sonication, subsequently, polycarbonate was precipitated gradually onto the surface of them to form the adsorbent. Extraction recoveries of 85% and 76%, enrichment factors of 57 and 51, limits of detection of 2.5 and 2.8 µg/L, and limits of quantification of 8.3 and 9.3 µg/L were obtained for imipramine and desipramine under the optimal conditions, respectively. In addition, relative standard deviations for intra- (n = 6) and inter-day (n = 5) precisions at two concentrations (50 and 100 µg/L of each analyte) were less than or equal to 4%. Short extraction time, good repeatability, high enrichment factors, and simplicity are the main advantages of the proposed method.

Time-Dependent Effects of Buspirone versus Desipramine on the 5-Choice Serial Reaction Time Task in Rats Reared in Social Isolation: Implication of Early Life Experience and Motoric Impulsivity.

BACKGROUND: Early life social experience and the function of the central serotonin (5-Hydroxytryptophan, 5-HT) system are involved in development of behavioral impulsivity in which individuals act without forethought or before all necessary information is available. However, most of the evidence has been obtained from acute 5-HT manipulation, whereas, the present study aimed to investigate the effects of subchronic regimen targeting of 5-HT1A receptors on motoric waiting impulsivity in socially isolated rats. METHODS: A two-week protocol of buspirone (0.5 mg/kg/day) and desipramine (2.5 mg/kg/day) was employed for rats following social isolation rearing (IR) to examine their behavioral performance in a 5-choice serial reaction time task (5-CSRTT) during the treatment regimen. Responses in any one of the apertures prior to an informative signal were recorded as a premature response. RESULTS: IR rats presented with more locomotor activity than socially reared (SR) rats. Buspirone progressively increased the baseline level of premature responding in a time-dependent manner that was not observed in IR rats. Both IR and SR rats exhibited less premature responding following acute buspirone challenge. For a subchronic desipramine regimen, IR rats followed the same trend of SR controls to increase the prematurity of baseline response. CONCLUSIONS: Buspirone but not desipramine-induced time-dependent effects of motoric waiting impulsivity can be reversed by IR, indicating a role for early life social experience on 5-HT1A receptor-associated ability to control impulsiveness.

Pharmacological Interventions for Primary Psychodermatologic Disorders: An Evidence Mapping and Appraisal of Randomized Controlled Trials.

BACKGROUND: The lack of clinical guidelines for the treatment of primary psychodermatologic disorders (PPDs) hinders the delivery of optimal care to patients. The review aimed to identify, appraise, and summarize the currently available evidence about the safety and effectiveness of pharmacological management of PPDs through randomized controlled trials (RCTs). METHODS: The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRIMSA) statement and the Global Evidence Mapping Initiative guidance were followed. Medline, Embase, PsycInfo, Cochrane and Scopus were searched, and two reviewers independently completed article review, data extraction, and quality assessment. RESULTS: Among 2618 unique studies, full texts of 83 were reviewed and 21 RCTs were included. Five PDDs were identified: trichotillomania (n = 12), pathologic skin picking (n = 5), nail biting (n = 2), delusional parasitosis (n = 1), and dermatitis from compulsive hand washing (n = 1). Seven different classes of medications were investigated: SSRIs (i.e., fluoxetine, sertraline, and citalopram), tricyclic antidepressants (i.e., clomipramine and desipramine), antipsychotics (i.e., olanzapine and pimozide), anticonvulsant (i.e., lamotrigine), N-acetylcysteine, inositol, and milk thistle. RCT-derived evidence supports the use of antidepressants in trichotillomania (sertraline and clomipramine), pathologic skin picking (fluoxetine), pathologic nail biting and dermatitis from compulsive hand washing (clomipramine or desipramine); antipsychotics in trichotillomania (olanzapine) and delusional parasitosis (pimozide); N-acetyl cysteine in trichotillomania and skin picking. CONCLUSION: Few pharmacotherapies for primary psychodermatologic disorders are assessed through controlled trials in the literature. This review serves as a roadmap for researchers and clinicians to reach informed decisions with current evidence, and to build on it to establish guidelines in the future.

Randomized Trial of Medical versus Surgical Treatment for Refractory Heartburn.

BACKGROUND: Heartburn that persists despite proton-pump inhibitor (PPI) treatment is a frequent clinical problem with multiple potential causes. Treatments for PPI-refractory heartburn are of unproven efficacy and focus on controlling gastroesophageal reflux with reflux-reducing medication (e.g., baclofen) or antireflux surgery or on dampening visceral hypersensitivity with neuromodulators (e.g., desipramine). METHODS: Patients who were referred to Veterans Affairs (VA) gastroenterology clinics for PPI-refractory heartburn received 20 mg of omeprazole twice daily for 2 weeks, and those with persistent heartburn underwent endoscopy, esophageal biopsy, esophageal manometry, and multichannel intraluminal impedance-pH monitoring. If patients were found to have reflux-related heartburn, we randomly assigned them to receive surgical treatment (laparoscopic Nissen fundoplication), active medical treatment (omeprazole plus baclofen, with desipramine added depending on symptoms), or control medical treatment (omeprazole plus placebo). The primary outcome was treatment success, defined as a decrease of 50% or more in the Gastroesophageal Reflux Disease (GERD)-Health Related Quality of Life score (range, 0 to 50, with higher scores indicating worse symptoms) at 1 year. RESULTS: A total of 366 patients (mean age, 48.5 years; 280 men) were enrolled. Prerandomization procedures excluded 288 patients: 42 had relief of their heartburn during the 2-week omeprazole trial, 70 did not complete trial procedures, 54 were excluded for other reasons, 23 had non-GERD esophageal disorders, and 99 had functional heartburn (not due to GERD or other histopathologic, motility, or structural abnormality). The remaining 78 patients underwent randomization. The incidence of treatment success with surgery (18 of 27 patients, 67%) was significantly superior to that with active medical treatment (7 of 25 patients, 28%; P = 0.007) or control medical treatment (3 of 26 patients, 12%; P<0.001). The difference in the incidence of treatment success between the active medical group and the control medical group was 16 percentage points (95% confidence interval, -5 to 38; P = 0.17). CONCLUSIONS: Among patients referred to VA gastroenterology clinics for PPI-refractory heartburn, systematic workup revealed truly PPI-refractory and reflux-related heartburn in a minority of patients. For that highly selected subgroup, surgery was superior to medical treatment. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT01265550.).

Acid sphingomyelinase deactivation post-ischemia promotes brain angiogenesis and remodeling by small extracellular vesicles.

Antidepressants have been reported to enhance stroke recovery independent of the presence of depressive symptoms. They have recently been proposed to exert their mood-stabilizing actions by inhibition of acid sphingomyelinase (ASM), which catalyzes the hydrolysis of sphingomyelin to ceramide. Their restorative action post-ischemia/reperfusion (I/R) still had to be defined. Mice subjected to middle cerebral artery occlusion or cerebral microvascular endothelial cells exposed to oxygen-glucose deprivation were treated with vehicle or with the chemically and pharmacologically distinct antidepressants amitriptyline, fluoxetine or desipramine. Brain ASM activity significantly increased post-I/R, in line with elevated ceramide levels in microvessels. ASM inhibition by amitriptyline reduced ceramide levels, and increased microvascular length and branching point density in wildtype, but not sphingomyelinase phosphodiesterase-1 ([Smpd1]-/-) (i.e., ASM-deficient) mice, as assessed by 3D light sheet microscopy. In cell culture, amitriptyline, fluoxetine, and desipramine increased endothelial tube formation, migration, VEGFR2 abundance and VEGF release. This effect was abolished by Smpd1 knockdown. Mechanistically, the promotion of angiogenesis by ASM inhibitors was mediated by small extracellular vesicles (sEVs) released from endothelial cells, which exhibited enhanced uptake in target cells. Proteomic analysis of sEVs revealed that ASM deactivation differentially regulated proteins implicated in protein export, focal adhesion, and extracellular matrix interaction. In vivo, the increased angiogenesis was accompanied by a profound brain remodeling response with increased blood-brain barrier integrity, reduced leukocyte infiltrates and increased neuronal survival. Antidepressive drugs potently boost angiogenesis in an ASM-dependent way. The release of sEVs by ASM inhibitors disclosed an elegant target, via which brain remodeling post-I/R can be amplified.

Effects of the LC mobile phase in vacuum differential mobility spectrometry-mass spectrometry for the selective analysis of antidepressant drugs in human plasma.

The effect of LC mobile phase composition and flow rate (2-50 µL/min) on mobility behavior in vacuum differential mobility spectrometry (vDMS) was investigated for electrosprayed isobaric antidepressant drugs (AD); amitriptyline, maprotiline, venlafaxine; and structurally related antidepressants nortriptyline, imipramine, and desipramine. While at 2 µL/min, no difference in compensation voltage was observed with methanol and acetonitrile, at 50 µL/min, acetonitrile used for LC elution of analytes enabled the selectivity of the mobility separation to be improved. An accurate and sensitive method could be developed for the quantification of six AD drugs in human plasma using trap/elute micro-LC setup hyphenated to vDMS with mass spectrometric detection in the selected ion monitoring mode. The assay was found to be linear over three orders of magnitude, and the limit of quantification was of 25 ng/mL for all analytes. The LC-vDMS-SIM/MS method was compared to a LC-MRM/MS method, and in both cases, inter-assay precisions were lower than 12.5 and accuracies were in the range 91.5-110%, but with a four times reduced analysis time (2 min) for the LC-vDMS-SIM/MS method. This work illustrates that with vDMS, the LC mobile phase composition can be used to tune the ion mobility separation and to improve assay selectivity without additional hardware.

Combined intervention with N-acetylcysteine and desipramine alleviated silicosis development by regulating the Nrf2/HO-1 and ASMase/ceramide signaling pathways.

Silicosis is a systemic disease characterized by diffuse fibrosis of the lung tissue caused by long-term inhalation of large amounts of free silica (SiO2) dust. The pathogenesis of silicosis has not been fully elucidated, and there is a lack of effective treatment methods. N-acetylcysteine (NAC) can potentially treat pulmonary fibrosis by exerting antioxidant effects. Desipramine (DMI) can influence pulmonary fibrosis development by inhibiting acid sphingomyelinase (ASMase) activity and regulating ceramide concentrations. Both can interfere with pulmonary fibrosis through different mechanisms, but the intervention effects of NAC combined with DMI on silicosis fibrosis have not been reported. Therefore, this study established a rat silicosis model using a single tracheal drip of SiO2 dust suspension in Wistar rats to investigate the effect of NAC combined with DMI on SiO2 dust-induced silicosis and its related molecular mechanisms. The histopathological examination of the SiO2 dust-induced silicosis rats suggested that NAC and DMI alone or in combination could decrease the severity of pulmonary fibrosis in rats. The combined intervention had a better effect on reducing fibrosis than the individual interventions. NAC and DMI, alone or in combination, decreased the levels of markers related to pulmonary fibrosis in rats (smooth muscle α-actin (α-SMA), collagen (Col) I, Col III, hydroxyproline (HYP), inflammatory factors (transforming growth factor-ß1 (TGF-ß1) and tumor necrosis factor-α (TNF-α)), and lipid peroxidase malondialdehyde (MDA)). The nuclear factor-erythroid 2-related factor 2 (Nrf2)/heme-oxygenase-1 (HO-1) and ASMase/ceramide pathways were inhibited to some extent by increasing the superoxide dismutase (SOD) levels of antioxidant enzymes and 8-iso-prostaglandin F2α (8-iso-PGF2α) levels of lipid peroxides. The combined intervention and NAC alone inhibited the SiO2 dust-induced elevation of matrix metalloproteinase 1 (MMP-1) and tissue inhibitor matrix metalloproteinase 1 (TIMP-1), but the effect was not significant in the DMI-treated group. Combining DMI and NAC inhibited Col I deposition and reduced HO-1, TIMP-1, and ASMase levels in lung tissues compared to individual treatments. In summary, the SiO2 dust could induce oxidative stress and inflammation in rats, resulting in an imbalance in extracellular matrix (ECM) synthesis/catabolism and ASMase/ceramide signaling pathway activation, leading to silicosis development.The combined intervention of DMI and NAC may synergistically regulate the Nrf2/HO-1 pathway, maintain the anabolic balance of the ECM, inhibit ASMase/ceramide signaling pathway activation by suppressing the inflammatory response and effectively delay silicosis fibrosis progression.

Calcium-Dependent Interplay of Lithium and Tricyclic Antidepressants, Amitriptyline and Desipramine, on N-methyl-D-aspartate Receptors.

The facilitated activity of N-methyl-D-aspartate receptors (NMDARs) in the central and peripheral nervous systems promotes neuropathic pain. Amitriptyline (ATL) and desipramine (DES) are tricyclic antidepressants (TCAs) whose anti-NMDAR properties contribute to their analgetic effects. At therapeutic concentrations <1 µM, these medicines inhibit NMDARs by enhancing their calcium-dependent desensitization (CDD). Li+, which suppresses the sodium−calcium exchanger (NCX) and enhances NMDAR CDD, also exhibits analgesia. Here, the effects of different [Li+]s on TCA inhibition of currents through native NMDARs in rat cortical neurons recorded by the patch-clamp technique were investigated. We demonstrated that the therapeutic [Li+]s of 0.5−1 mM cause an increase in ATL and DES IC50s of ~10 folds and ~4 folds, respectively, for the Ca2+-dependent NMDAR inhibition. The Ca2+-resistant component of NMDAR inhibition by TCAs, the open-channel block, was not affected by Li+. In agreement, clomipramine providing exclusively the NMDAR open-channel block is not sensitive to Li+. This Ca2+-dependent interplay between Li+, ATL, and DES could be determined by their competition for the same molecular target. Thus, submillimolar [Li+]s may weaken ATL and DES effects during combined therapy. The data suggest that Li+, ATL, and DES can enhance NMDAR CDD through NCX inhibition. This ability implies a drug−drug or ion−drug interaction when these medicines are used together therapeutically.

Clinical practice guideline on pharmacological and psychological management of adult patients with an anxiety disorder and comorbid substance use. / Guía de práctica clínica para el tratamiento farmacológico y psicológico de los pacientes adultos con un trastorno de ansiedad y un diagnóstico comórbido de trastorno por uso de sustancias.

This review synthesizes the pharmacological and psychosocial interventions that have been conducted in comorbid anxiety disorders and SUDs while also providing clinical recommendations about which intervention elements are helpful for addressing substance use versus anxiety symptoms in patients with these co-occurring conditions. The best evidence from randomized controlled trials was used to evaluate treatment options. The strength of recommendations was described using the GRADE approach. Clinical trials are only available for posttraumatic stress disorder (PTSD) and for social anxiety. Concerning the comorbid substance use, all the studies have included patients with alcohol use, none of them have dealt with cocaine, cannabis or nicotine use. Although some treatments have shown benefit for anxiety symptoms without benefits for alcohol or other substance use, only limited pharmacological approaches have been assayed (sertraline, desipramine, paroxetine, buspirone, naltrexone and disulfiram). Our results suggest that 1) we can (weakly) recommend the use of desipramine over paroxetine to alleviate symptoms of anxiety in patients with a PTSD and alcohol use; 2) In these patients, the use of naltrexone to reduce symptoms of anxiety is also recommended (weak strength); and 3) SSRI antidepressants vs placebo can be recommended to reduce alcohol use (weak recommendation). Our review highlights the need for more research in this area and for larger, multisite studies with generalizable samples to provide more definite guidance for clinical practice.

Esta revisión resume las intervenciones farmacológicos y psicosociales que han sido llevadas a cabo en trastornos de ansiedad con un diagnóstico comórbido de trastorno por uso de sustancias y además proporciona recomendaciones clínicas respecto de cuáles elementos de intervención son útiles para hacer frente a los síntomas del uso de sustancias y los síntomas de ansiedad en pacientes con estas afecciones concurrentes. Se utilizó la mejor evidencia de ensayos controlados aleatorizados para evaluar las opciones de tratamiento. La fuerza de las recomendaciones se describió mediante el enfoque GRADE. Hay ensayos clínicos disponibles únicamente para el trastorno por estrés postraumático (TEPT) y para el trastorno de ansiedad. En cuanto al diagnóstico comórbido de trastorno por uso de sustancias, todos los estudios han incluido pacientes con consumo de alcohol, ninguno de ellos ha abordado el consumo de cocaína, cannabis o nicotina. Aunque algunos tratamientos han mostrado beneficios para los síntomas de ansiedad sin beneficios para el consumo de alcohol u otras sustancias, solo se han ensayado enfoques farmacológicos limitados (sertralina, desipramina, paroxetina, buspirona, naltrexona y disulfiram). Nuestros resultados sugieren que 1) podemos (débilmente) recomendar el uso de desipramina sobre la paroxetina para aliviar los síntomas de ansiedad en pacientes con un TEPT y consumo de alcohol; 2) en estos pacientes, el uso de naltrexona para reducir los síntomas de ansiedad es también recomendable (fuerza débil); y 3) se pueden recomendar antidepresivos ISRS frente a placebo para reducir el consumo de alcohol (recomendación débil). Nuestra revisión pone de relieve la necesidad de realizar más investigaciones en esta área y de estudios más grandes, multisitio con muestras generalizables para proporcionar evidencia más definitiva para la práctica clínica.

Enhanced sympathetic neurotransduction in the superior mesenteric artery in a rat model of heart failure: role of noradrenaline and ATP.

Heart failure (HF) is associated with neurohumoral activation, which in turn leads to an increased peripheral resistance. In mesenteric vasculature, perivascular innervation plays relevant role maintaining vascular tonus and resistance. Therefore, we aimed to determine the possible alterations in superior mesenteric artery (SMA) perivascular innervation function in HF rats. HF was induced by coronary artery occlusion in male Wistar rats, and sham-operated (SO) rats were used as controls. After 12 wk, a greater vasoconstrictor response to electrical field stimulation (EFS) was observed in endothelium-intact and endothelium-denuded SMA of HF rats. Alpha-adrenoceptor antagonist phentolamine diminished this response in a higher magnitude in HF than in SO animals. However, the noradrenaline (NA) reuptake inhibitor desipramine increased EFS-induced vasoconstriction more in segments from HF rats. Besides, EFS-induced NA release was greater in HF animals, due to a higher tyrosine hydroxylase expression and activity. P2 purinoceptor antagonist suramin reduced EFS-induced vasoconstriction only in segments from SO rats, and adenosine 5'-triphosphate (ATP) release was lower in HF than in SO. Moreover, nitric oxide (NO) synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME) enhanced EFS-induced vasoconstriction in a similar extent in both groups. HF was not associated with changes in EFS-induced NO release or the vasodilator response to NO donor sodium nitroprusside. In conclusion, HF postmyocardial infarction enhanced noradrenergic function and diminished purinergic cotransmission in SMA and did not change nitrergic innervation. The net effect was an increased sympathetic participation on the EFS-induced vasoconstriction that could help to understand the neurotransduction involved on the control of vascular tonus in HF.NEW & NOTEWORTHY This study reinforces the pivotal role of noradrenergic innervation in the regulation of mesenteric vascular tone in a rat model of heart failure. Moreover, our results highlight the counteracting role of ATP and NA reuptake, and help to understand the signaling pathways involved on the control of vascular tonus and resistance in heart failure postmyocardial infarction.

Facilitation of dopamine-dependent long-term potentiation in the medial prefrontal cortex of male rats follows the behavioral effects of stress.

The effect of stress on animal behavior and brain activity has been attracting growing attention in the last decades. Stress dramatically affects several aspects of animal behavior, including motivation and cognitive functioning, and has been used to model human pathologies such as post-traumatic stress disorder. A key question is whether stress alters the plastic potential of synaptic circuits. In this work, we evaluated if stress affects dopamine (DA)-dependent synaptic plasticity in the medial prefrontal cortex (mPFC). On male adolescent rats, we characterized anxiety- and depressive-like behaviors using behavioral testing before and after exposure to a mild stress (elevated platform, EP). After the behavioral protocols, we investigated DA-dependent long-term potentiation (DA-LTP) and depression (DA-LTD) on acute slices of mPFC and evaluated the activation of DA-producing brain regions by western and dot blot analysis. We show that exposure to the EP stress enhances DA-LTP and that desipramine (DMI) treatment abolishes this effect. We also found that DA-LTD is not affected by EP stress unless when this is followed by DMI treatment. In addition, EP stress reduces anxiety, an effect abolished by both DMI and ketamine, while motivation is promoted by previous exposure to EP stress independently of pharmacological treatments. Finally, this form of stress reduces the expression of the early gene cFOS in the ventral tegmental area. These findings support the idea that mild stressors can promote synaptic plasticity in PFC through a dopaminergic mechanism, an effect that might increase the sensitivity of mPFC to subsequent stressful experiences.

Divergent membrane properties of mouse cochlear glial cells around hearing onset.

Spiral ganglion neurons (SGNs) are the primary afferent neurons of the auditory system, and together with their attendant glia, form the auditory nerve. Within the cochlea, satellite glial cells (SGCs) encapsulate the cell body of SGNs, whereas Schwann cells (SCs) wrap their peripherally- and centrally-directed neurites. Despite their likely importance in auditory nerve function and homeostasis, the physiological properties of auditory glial cells have evaded description. Here, we characterized the voltage-activated membrane currents of glial cells from the mouse cochlea. We identified a prominent weak inwardly rectifying current in SGCs within cochlear slice preparations (postnatal day P5-P6), which was also present in presumptive SGCs within dissociated cultures prepared from the cochleae of hearing mice (P14-P15). Pharmacological block by Ba2+ and desipramine suggested that channels belonging to the Kir4 family mediated the weak inwardly rectifying current, and post hoc immunofluorescence implicated the involvement of Kir4.1 subunits. Additional electrophysiological profiles were identified for glial cells within dissociated cultures, suggesting that glial subtypes may have specific membrane properties to support distinct physiological roles. Immunofluorescence using fixed cochlear sections revealed that although Kir4.1 is restricted to SGCs after the onset of hearing, these channels are more widely distributed within the glial population earlier in postnatal development (i.e., within both SGCs and SCs). The decrease in Kir4.1 immunofluorescence during SC maturation was coincident with a reduction of Sox2 expression and advancing neurite myelination. The data suggest a diversification of glial properties occurs in preparation for sound-driven activity in the auditory nerve.

Gelatin microsphere coated Fe3O4@graphene quantum dots nanoparticles as a novel magnetic sorbent for ultrasound-assisted dispersive magnetic solid-phase extraction of tricyclic antidepressants in biological samples.

Gelatin microsphere-coated Fe3O4@graphene quantum dots (Fe3O4@GQD@GM) were designed and synthesized as a novel sorbent via ultrasonic-assisted dispersive magnetic solid-phase extraction (UA-DMSPE) method. The synthesized sorbent was identified and confirmed by FT-IR, XRD, VSM, and SEM techniques. UA-DMSPE was combined with corona discharge ion mobility spectrometry for trace determination of desipramine, sertraline, and citalopram. Effective parameters were considered and optimized. The proposed method, under optimal conditions, showed excellent linearity in different concentration ranges (2-700 ng mL-1, R2 > 0.995), repeatability (RSD < 5.1%), good sensitivity (LODs in the range 0.6-1.5 ng mL-1), high preconcentration factor (PF = 207-218), and acceptable relative recoveries (93.5-101.8%). Eventually, this method was used to determine tricyclic antidepressants in various biological samples. Schematic presentation of the microextraction and monitoring of TCAs by ultrasonic-assisted dispersive magnetic solid phase microextraction-ion mobility spectrometry producer.