Biological rationale and potential clinical use of gabapentin and pregabalin in bipolar disorder, insomnia and anxiety: protocol for a systematic review and meta-analysis

Efficacy and safety of acupuncture therapy combined with conventional pharmacotherapy in the treatment of systemic lupus erythematosus: A systematic review and meta-analysis

BACKGROUND

Currently, the mainstream treatments for systemic lupus erythematosus (SLE) are based on glucocorticoids and immunosuppressants, which are known to have considerable adverse effects. This meta-analysis is aimed at confirming the efficacy and safety of acupuncture therapy in combination with traditional medications in the treatment of SLE.

METHODS

Multiple databases were searched for randomized controlled trials using acupuncture therapy in combination with conventional pharmacotherapy for the treatment of SLE, from the establishment of the database to March 2023. Study selection, data collection, as well as quality assessment were conducted by 2 reviewers independently. RevMan 5.4 and Stata 17 software were used for Meta-analysis.

RESULTS

Seven eligible studies involving 514 patients with SLE were included. Meta-analysis demonstrated that in SLE patients, extra treatment with acupuncture was superior to drug therapy alone in improving the overall response rate (RR = 1.20, 95% confidence intervals [1.11, 1.29], P < .00001, heterogeneity P = .69, I2 = 0%) and regulating immunological indicators (C3, C4, IgG, T lymphocyte subpopulation, IL-6, ds-DNA, ESR) while reducing TCM symptom scores, the SLE Disease Activity Index (SLEDAI) and the incidence of adverse events on treatment (P ≤ 0.05). Additionally, it was able to reduce BUN, Scr and 24 hours urine protein, suggesting that acupuncture treatment had a protective effect on the kidneys.

CONCLUSIONS

Acupuncture therapy combined with conventional pharmacotherapy is an efficient and safe way in the treatment of SLE. However, the conclusions drawn from this meta-analysis have some limitations due to the small number and uneven quality of the included studies, leading to heterogeneity and bias. Thus more relevant high-quality randomized controlled trials are needed for further evaluation in the future.

Efficacy and safety of Qi and Blood Tonic Chinese Medicines in the treatment of COVID-19: A protocol for systematic review and meta-analysis

BACKGROUND

Coronavirus disease in 2019 (COVID-19) is a sudden public event affecting all human beings, with the rapid transmission, extensive groups affected, many complications, and high mortality. Traditional Chinese Medicine has a long history of preventing and treating infectious diseases, and numerous studies have shown that Traditional Chinese Medicine, especially herbal medicine, has a positive effect on the prevention, treatment, and post-healing recovery of this COVID-19, and herbal medicines to supplement qi and blood often occupy a certain proportion of it. However, there is no relevant meta-analysis to date. Therefore, this study aims to evaluate the efficacy and safety of qi and blood tonic herbal medicines in the treatment of COVID-19 through Systematic Review and meta-analysis to provide a reference basis for widespread clinical application.

METHODS

We will search from the following databases for the period from the time of database construction to March 1st, 2023. The English databases include: PubMed, MEDLINE, EMBASE, Cochrane library, WOS, Google Scholar, and CENTRAL; The Chinese databases include: China National Knowledge Infrastructure, China Biomedical Literature Database, Technology Journal Database, and Wanfang. Randomized controlled trials in English or Chinese that include Chinese herbal medicines for tonifying Qi and Blood in the treatment of patients with COVID-19 will be included. Data were independently screened and collected by 2 investigators. The risk of bias for each trial was assessed using the Cochrane Risk of Bias Tool 2.0. RevMan 5.3 software was used for the meta-analysis of the data. Primary outcome indicators included cure, mortality, and exacerbation rates (change in disease severity category, patient admission to ICU, etc.). Secondary outcome indicators included recovery rate or duration of major symptoms (e.g., fever, cough, fatigue, and weakness, etc.), rate or duration of nucleic acid conversion for severe acute respiratory syndrome coronavirus-2, improvement or recovery of chest CT performance, length of hospital stay, and other adverse events.

RESULTS

This protocol adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-P guidelines to ensure clarity and completeness of reporting in all phases of the systematic review.

CONCLUSION

This study will provide evidence regarding the efficacy and safety of Qi and Blood Tonic Chinese Medicines for the treatment of COVID-19.

PROSPERO REGISTRATION NUMBER

CRD42022361822 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022361822).

Chronic Nodular Prurigo: An Update on the Pathogenesis and Treatment

Chronic nodular prurigo (CNPG) is a recalcitrant chronic itchy disorder that affects the quality of life. It can be triggered by multiple etiologies, such as atopic dermatitis, diabetes, and chronic renal diseases. The mechanisms of CNPG are complicated and involved the interaction of the cutaneous, immune, and nervous systems. Diverse immune cells, including eosinophils, neutrophils, T cells, macrophages, and mast cells infiltrated the lesional skin of CNPG, which initiated the inflammatory cytokines and pruritogens release. In addition, the interaction between the immune cells and activated peripheral sensory nerve fibers by neurotransmitters caused neuroinflammation in the skin and intractable itch. This itch-scratch vicious cycle of CNPG results in disease exacerbation. CNPG is difficult to treat with traditional therapies. Recently, great advances have been made in the pathophysiology of both inflammation and pruritus transmission in CNPG. In this review, we summarize the updated mechanisms and novel therapies for CNPG.

HPLC Analytical Method Development and Validation of Gabapentin through Chemical Derivatization with Catechol as a Chromophore

Background

Gabapentin is a drug with anticonvulsant activity and has been widely used in the treatment of epilepsy. Gabapentin chemical structure lacks a chromophore which makes its absorption very low and hence complicates its analysis and reduces the sensitivity of the method. Adding a chromophore by chemical derivatization makes the drug easily identified and quantified at a much lower concentration using chromatographic analysis such as HPLC. Methodology. The derivatization of gabapentin was done by adding a chromophore to the structure by introducing an auxochrome group. Suitable coupling reagents were used to introduce catechol group to gabapentin. The analytical method has been developed using HPLC with UV/Vis detector. Moreover, the method was validated for parameters such as linearity, range, precision, accuracy, LOD, and LOQ.

Result

The developed method adapted derivatization of gabapentin using catechol reagent measured at λmax 300 nm. The method used HPLC using mobile phase methanol water 50 : 50. The eluted peak of the derivatized gabapentin was separated from other used derivatization reagents. The analytical method showed to be a validated method, and all the tested validation parameters were within the accepted limits. The developed method was found to be linear (R² = 0.9917), precise (RSD = 0.91) and accurate (% recovery = 105). Moreover, the developed method was sensitive with LOD (0.5^∗10⁻⁶ mg/mL) and LOQ (1.5^∗10⁻⁶ mg/mL).

Conclusion

The developed method is simple and feasible with high sensitivity and selectivity. It can be applied in the analysis of gabapentin in different dosage forms and raw materials including active pharmaceutical ingredients (API). This research work can be continued in the future, and the developed method can be used for testing gabapentin in biological systems.

The potential mechanism of Bupleurum against anxiety was predicted by network pharmacology study and molecular docking

Bupleurum chinense DC. (Chaihu) is a traditional Chinese medicine (TCM) used in the treatment of anxiety. But the anxiolytic mechanisms of bupleurum are still unclear. Therefore, this unknown is predicted by network pharmacology study with molecular docking in the present study. The components of bupleurum were obtained from the databases. Genes associated with components and disease were also provided by databases. Overlapping genes between components and disease were analyzed. The network of medicine-components-targets-disease was constructed, visualized, and analyzed. Protein-protein interaction (PPI), gene ontology (GO), pathway enrichment (KEGG) and molecular docking were conducted to predict the potential mechanisms of bupleurum on anxiety. A total of 9 bioactive components derived from bupleurum with 80 target genes were involved in anxiety. Neurotransmitter receptor activity, G protein-coupled amine receptor activity, regulation of blood circulation, neuroactive ligand-receptor interaction, calcium signaling pathway and salivary secretion may play significant roles in the anxiolytic of bupleurum. Molecular docking implicated that ACHE and MAOA showed high affinity for stigmasterol. Based on network pharmacology study with molecular docking, multi-component-multi-target-multi-pathway action mode of bupleurum on anxiety was elaborated. Stigmasterol might be the core bioactive component, while ACHE and MAOA might be the core target genes in the pharmacological profile of bupleurum on anxiety.

Effects of tai chi and qigong on rehabilitation after COVID-19: a protocol for systematic review and meta-analysis

INTRODUCTION

COVID-19 is a public health emergency of international concern, which is characterised by rapid and widespread transmission, high mortality and complications. Several studies have shown the benefits of tai chi and qigong for recovery after COVID-19; however, no meta-analysis has been reported. Therefore, the purpose of this study is to evaluate the efficacy and safety of tai chi and/or qigong on rehabilitation after COVID-19 through a systematic review and meta-analysis to provide a reference and basis for clinical application.

METHODS AND ANALYSIS

This study will use the Cochrane Library, PubMed, Web of Science, Embase, China Knowledge Network, China Biomedical Literature Database, Chinese Scientific Journal Database and Wanfang Database. The time period is from the inception of the database to November 2021, with no language restrictions. Searches will be conducted using the subject terms "Taichi","Qigong" and "COVID-19" plus free-text words. Articles will be screened and collected by two reviewers independently. Included studies will be assessed for quality using the Cochrane Risk of Bias Assessment Tool. Statistical analyses will be performed using the Revman V.5.3 software. The primary outcomes include 1-second forced expiratory volume and 1-second forced vital capacity, oxygen saturation, total white cell count and quality of life score. Secondary outcomes include time to remission of major symptoms, incidence of adverse events, clinical cure rate and mortality. Subgroup and sensitivity analyses will also be used to explore and interpret the heterogeneity. This protocol is written based on the guideline of the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocol.

ETHICS AND DISSEMINATION

Ethical approval and consent are unnecessary because no primary data will be collected. The results will be disseminated through peer-reviewed publications.

PROSPERO REGISTRATION NUMBER

CRD42021288962.

Pregabalin abuse and dependence during insomnia and protocol for short-term withdrawal management with diazepam: examples from case reports

Introduction:

Pregabalin (PGN) is an anxiolytic, analgesic, antiepileptic, and hypnotic medication. There are concerns about its abuse in the community for managing chronic insomnia and other risks when assumed in overdose or combination with other abuse substances. PGN is classified as a controlled medication. While its discontinuation is accompanied by rebound insomnia and other neurological symptoms, cross-tapering PGN with short-term diazepam (DZ) during inpatient admissions has shown promising results in dealing with PGN withdrawal symptoms accompanied by rebound insomnia.

Material and Methods:

We report three cases that began abusing their prescribed PGN. During hospital admission, our teams used a protocol for cross-tapering PGN with DZ to reduce withdrawal symptoms. Other sedative medications are suspended while alcohol is not allowed if patients are on leave from the hospital. Standardized scales for assessment were clinical global impression scale-severity (CGI-S), generalized anxiety disorder scale (GAD-7), and insomnia severity index (ISI).

Results:

The cross-tapering PGN with DZ showed similar clinical outcomes with reduced withdrawal symptoms and rebound insomnia during two weeks of cross-tapering. Eventually, DZ, too, is stopped in the hospital to avoid another dependence syndrome.

Conclusion:

As emerging in the current study, PGN has strong addictive effects in people who have insomnia and is mostly abused for its hypnotic or sleep-inducing properties when other medications have failed. As applied in the current study, DZ can manage PGN withdrawal symptoms with rebound insomnia while cross-tapering. DZ is then discontinued.

Gabapentin and pregabalin in bipolar disorder, anxiety states, and insomnia: Systematic review, meta-analysis, and rationale

The gabapentinoids, gabapentin, and pregabalin, target the α₂δ subunits of voltage-gated calcium channels. Initially licensed for pain and seizures, they have become widely prescribed drugs. Many of these uses are off-label for psychiatric indications, and there is increasing concern about their safety, so it is particularly important to have good evidence to justify this usage. We conducted a systematic review and meta-analysis of the evidence for three of their common psychiatric uses: bipolar disorder, anxiety, and insomnia. Fifty-five double-blind randomised controlled trials (RCTs) and 15 open-label studies were identified. For bipolar disorder, four double-blind RCTs investigating gabapentin, and no double-blind RCTs investigating pregabalin, were identified. A quantitative synthesis could not be performed due to heterogeneity in the study population, design and outcome measures. Across the anxiety spectrum, a consistent but not universal effect in favour of gabapentinoids compared to placebo was seen (standardised mean difference [SMD] ranging between -2.25 and -0.25). Notably, pregabalin (SMD -0.55, 95% CI -0.92 to -0.18) and gabapentin (SMD -0.92, 95% CI -1.32 to -0.52) were more effective than placebo in reducing preoperative anxiety. In insomnia, results were inconclusive. We conclude that there is moderate evidence of the efficacy of gabapentinoids in anxiety states, but minimal evidence in bipolar disorder and insomnia and they should be used for these disorders only with strong justification. This recommendation applies despite the attractive pharmacological and genetic rationale for targeting voltage-gated calcium channels.

Results from a randomized, double-blind, placebo-controlled, crossover, multimodal-MRI pilot study of gabapentin for co-occurring bipolar and cannabis use disorders

Disrupted brain gamma-aminobutyric acid (GABA)/glutamate homeostasis is a promising target for pharmacological intervention in co-occurring bipolar disorder (BD) and cannabis use disorder (CUD). Gabapentin is a safe and well-tolerated medication, FDA-approved to treat other neurological diseases, that restores GABA/glutamate homeostasis, with treatment studies supporting efficacy in treating CUD, as well as anxiety and sleep disorders that are common to both BD and CUD. The present manuscript represents the primary report of a randomized, double-blind, placebo-controlled, crossover (1-week/condition), multimodal-MRI (proton-MR spectroscopy, functional MRI) pilot study of gabapentin (1200 mg/day) in BD + CUD (n = 22). Primary analyses revealed that (1) gabapentin was well tolerated and adherence and retention were high, (2) gabapentin increased dorsal anterior cingulate cortex (dACC) and right basal ganglia (rBG) glutamate levels and (3) gabapentin increased activation to visual cannabis cues in the posterior midcingulate cortex (pMCC, a region involved in response inhibition to rewarding stimuli). Exploratory evaluation of clinical outcomes further found that in participants taking gabapentin versus placebo, (1) elevations of dACC GABA levels were associated with lower manic/mixed and depressive symptoms and (2) elevations of rBG glutamate levels and pMCC activation to cannabis cues were associated with lower cannabis use. Though promising, the findings from this study should be interpreted with caution due to observed randomization order effects on dACC glutamate levels and identification of statistical moderators that differed by randomization order (i.e. cigarette-smoking status on rBG glutamate levels and pMCC cue activation). Nonetheless, they provide the necessary foundation for a more robustly designed (urn-randomized, parallel-group) future study of adjuvant gabapentin for BD + CUD.

Effect of Acupuncture on Cognitive Function of Insomnia Patients Compared with Drugs: A Protocol for Meta-analysis and Systematic Review

Insomnia, one of the most common sleep disorders, is thought to have an adverse effect on cognitive function. At the same time, people with cognitive dysfunction are more prone to insomnia. At present, pharmacotherapy is the main treatment for insomnia, but there are some shortcomings such as poor long-term efficacy and potential dependence. There is some evidence that acupuncture has some advantages in alleviating insomnia and improving cognitive function. This study is aimed at investigating the effects of acupuncture and drugs on cognitive function in patients with insomnia and evaluating the efficacy and safety of these two interventions, providing strong evidence for clinical decision-making. The study will retrieve eight major databases: China National Knowledge Infrastructure, Wanfang Database, VIP Database for Chinese Technical Periodicals, SinoMed, PubMed, Web of Science, Embase, and Cochrane Library. Dissertations, conference papers, and ongoing experiments will also be retrieved for supplement. Literature screening and data extraction will be completed by two authors independently (JJ and X-QW). If there were any disagreements, they would be discussed or referred to a third person for adjudication (W-ZW). Authors will use Cochrane risk of bias tool to assess the included studies. The Review Manager Statistical (RevMan) software is used to conduct the statistical process of meta-analysis, and funnel plot is used to evaluate reporting biases. The Grading of Recommendations Assessment Development and Evaluation (GRADE) Profiler can be used to be aware of the quality of evidence.

A Systematic Review of the Clinical Use of Gabapentin and Pregabalin in Bipolar Disorder

Despite its prevalence and disease burden, several chasms still exist with regard to the pharmacotherapy of bipolar disorder (BD). Polypharmacy is commonly encountered as a significant proportion of patients remain symptomatic, and the management of the depressive phase of the illness is a particular challenge. Gabapentin and pregabalin have often been prescribed off-label in spite of a paucity of evidence and clinical practice guidelines to support its use. This systematic review aimed to synthesize the available human clinical trials and inform evidence-based pharmacological approaches to BD management. A total of six randomized, controlled trials (RCTs) and 13 open-label trials involving the use of gabapentin and pregabalin in BD patients were reviewed. Overall, the studies show that gabapentin and its related drug pregabalin do not have significant clinical efficacy as either monotherapy or adjunctive therapy for BD. Gabapentin and pregabalin are probably ineffective for acute mania based on the findings of RCT, with only small open-label trials to support its potential adjunctive role. However, its effects on the long-term outcomes of BD remain to be elucidated. The evidence base was significantly limited by the generally small sample sizes and the trials also had heterogeneous designs and generally high risk of bias.

Drug-drug Interactions between COVID-19 Treatments and Antidepressants, Mood Stabilizers/Anticonvulsants, and Benzodiazepines: Integrated Evidence from 3 Databases

INTRODUCTION

The SARS-CoV-2 pandemic with psychiatric comorbidities leads to a scenario in which the use of psychotropic drugs may be required. This requires the support of evidence-based medicine to take into account possible interactions between antidepressants, mood stabilizers, benzodiazepines, and coronavirus infection treatments.

METHODS

Three databases were consulted: (a) Lexicomp Drug Interactions, (b) Micromedex Solutions Drugs Interactions, (c)Liverpool Drug Interaction Group for COVID-19 therapies. The CredibleMeds QTDrugs List was also queried. Hydroxychloroquine, chloroquine, azithromycin, lopinavir-ritonavir, remdesivir, favipiravir, tocilizumab, baricitinib, anakinra, and dexamethasone - drugs used for SARS-CoV-2 - were analyzed, and consensus recommendations are made.

RESULTS

The potential interactions of agomelatine, desvenlafaxine, duloxetine, milnacipran, and vortioxetine with COVID-19 treatments shall be considered less risky. Antidepressant interactions with hydroxychloroquine, chloroquine, and azithromycin enhance the risk of QT prolongation, and ECG monitoring is advised for most antidepressants. Antidepressants with lopinavir/ritonavir involve multiple CYP enzyme interactions (except with milnacipran). Gabapentin, oxcarbazepine, pregabalin, topiramate, and zonisamide are safe treatment options that have no significant interactions with COVID-19 treatments. Lithium is contraindicated with hydroxychloroquine, chloroquine, and azithromycin. Precaution should be taken in using valproic acid with lopinavir-ritonavir. The use of benzodiazepines does not present a risk of drug interaction with COVID-19 treatments, except lopinavir/ritonavir.

CONCLUSIONS

Clinicians prescribing antidepressants, mood stabilizers/anticonvulsants, and benzodiazepines, should be aware of the probable risk of drug-drug interaction with COVID-19 medications and may benefit from heeding these recommendations for use to ensure patient safety.

Cellular calcium in bipolar disorder: systematic review and meta-analysis

Calcium signalling has long been implicated in bipolar disorder, especially by reports of altered intracellular calcium ion concentrations ([Ca²⁺]). However, the evidence has not been appraised critically. We carried out a systematic review and meta-analysis of studies of cellular calcium indices in bipolar disorder. 2281 records were identified and 117 screened, of which 32 were eligible and 21 were suitable for meta-analyses. The latter each involved up to 642 patients and 404 control subjects. We found that basal free intracellular [Ca²⁺] is increased in bipolar disorder, both in platelets and in lymphocytes. The effect size is 0.55, with an estimated elevation of 29%. It is observed in medication-free patients. It is present in mania and bipolar depression, but data are equivocal for euthymia. Cells from bipolar disorder individuals also show an enhanced [Ca²⁺] response to stimulation with 5-HT or thrombin, by an estimated 25%, with an effect size of 0.63. In studies which included other diagnoses, intracellular basal [Ca²⁺] was higher in bipolar disorder than in unipolar depression, but not significantly different from schizophrenia. Functional parameters of cellular Ca²⁺ (e.g. calcium transients), and neuronal [Ca²⁺], have been much less investigated, and no firm conclusions can be drawn. In summary, there is a robust, medium effect size elevation of basal and stimulated free intracellular [Ca²⁺] in bipolar disorder. The results suggest altered calcium functioning in the disorder, and encourage further investigations into the underlying mechanisms, and the implications for pathophysiology and therapeutics.

Usage of antiepileptic drugs in different diseases in Germany - A retrospective study

AIM

The goal of this study was to analyze and quantify the usage of antiepileptic drugs (AEDs) in different diseases and settings in Germany.

METHODS

This retrospective study, based on data from the Disease Analyzer database (IQVIA), included patients from 550 general practices (GP) and 73 neurological practices. Patients who had received at least one prescription for AED from one of these practices between January 2009 and December 2011 (time period 1, n = 39,434) or between January 2016 and December 2018 (time period 2, n = 49,128) were analyzed.

RESULTS

In patients who received AED prescriptions from neurologists, epilepsy (43%) was the most common diagnosis and did not change over time. The proportion of pain diagnoses slightly decreased from 35% in the period from 2009 to 2011 to 34% in the period from 2016 to 2018, while psychiatric disorders increased from 13% to 15%. In GPs, 58% of patients received their AED prescriptions for pain disorders, followed by epilepsy (29%) in the period from 2009 to 2011. The proportion of pain patients slightly increased to 60%, while that of patients with epilepsy slightly decreased to 27%.

CONCLUSIONS

The main indications for which AEDs are prescribed vary with the type of medical practice. The different indications for different AEDs changed between the two time periods, which is in line with the state of the research.

Effects of Stress on Itch

PURPOSE

Psychological stress and ensuing modulation of the immune and nervous systems can have a significant impact on itch. Stress can exacerbate itch and vice versa, resulting in a vicious cycle that can greatly impair a patient's quality of life. This review summarizes the association between stress and itch, elucidates the mechanism by which these two phenomena influence one another, and explores treatment modalities that aim to reduce stress-induced itch.

METHODS

A complete search of the PubMed and Google Scholar databases was completed and literature pertinent to this review was compiled.

FINDINGS

Both acute and chronic stress can significantly affect itch in healthy individuals and in those diagnosed with itchy skin diseases as well as systemic diseases, thus resulting in a vicious cycle in which stress exacerbates itch and vice versa. The mechanisms by which stress induces or aggravates itch include both central and peripheral activation of the hypothalamic-pituitary-adrenal axis and sympathetic nervous system. Activation of these systems, in turn, affects the mast cells, keratinocytes, and nerves that secrete neuropeptides, such as substance P, nerve growth factor, acetylcholine, histamine, and itchy cytokines. A dysfunctional parasympathetic response is thought to be involved in the chronic stress/itch response. Brain structures associated with emotion, such as the limbic system and periaqueductal gray, which work on the descending facilitation of itch, play a significant role in stress-induced itch.

IMPLICATIONS

As specific brain structures are associated with stress, drug treatments targeting these areas (ie, γ-aminobutyric acid-ergic drugs, serotonin and norepinephrine reuptake inhibitors) may help to modulate itch. Stress can also be combatted using nonpharmacologic treatments such as cognitive-behavioral therapies and stress-relieving holistic approaches (eg, yoga, acupuncture).

Pregabalin inhibits in vivo and in vitro cytokine secretion and attenuates spleen inflammation in Lipopolysaccharide/Concanavalin A -induced murine models of inflammation

Immune system alteration has been implicated in the pathogenesis of chronic pain conditions, epilepsy and generalized anxiety disorder. Targeting cytokines has recently been proposed for the management of such conditions. Pregabalin (PGB) is an antiepileptic agent used for the management of these conditions. However, little is known about its immunomodulatory effects on cytokine secretion in vivo and in vitro. Hence, a mitogen (Lipopolysaccharide [LPS] or Concanavalin A [ConA])-induced murine model of inflammation was used to investigate the effect of PGB on in vivo and in vitro IL-1β, IL-6, TNF-α and IL-2 cytokine secretion using ELISA. In addition, PGB effect on spleen histology, as a lymphoid organ, was examined. Our results revealed that PGB significantly inhibited the secretion of ConA-induced IL-6 secretion, basal and ConA-induced TNF-α and IL-2 secretion in splenocytes in vitro. In vivo, PGB inhibited basal and LPS/ConA-induced IL-6 and TNF-α secretion in addition to LPS-induced IL-1β and ConA-induced IL-2 secretion. Moreover, PGB attenuated mitogen-induced inflammatory changes in the spleen. These findings provide an evidence of the anti-inflammatory properties of PGB on cytokine secretion and lymphoid organ inflammation. This might give insights into the role of PGB in the management of the inflammatory state in PGB-indicated conditions.

The Emerging Neurobiology of Bipolar Disorder

(Reprinted with permission from Trends in Neurosciences, January 2018, Vol. 41, No. 1 ).

Feline hyperaesthesia syndrome with self-trauma to the tail: retrospective study of seven cases and proposal for an integrated multidisciplinary diagnostic approach

CASE SERIES SUMMARY

This was a retrospective study on the clinical features and response to treatment in seven cats with feline hyperaesthesia syndrome (FHS) and tail mutilation. FHS is a poorly understood disorder characterised by skin rippling over the dorsal lumbar area, episodes of jumping and running, excessive vocalisation, and tail chasing and self-trauma. The majority of the cats were young, with a median age of 1 year at the onset of clinical signs, male (n = 6) and with access to the outdoors (n = 5). Multiple daily episodes of tail chasing and self-trauma were reported in five cats, with tail mutilation in four cats. Vocalisation during the episodes (n = 5) and rippling of lumbar skin (n = 5) were also reported. Haematology, serum biochemistry, Toxoplasma gondii and feline immunodeficiency virus/feline leukaemia virus serology, MRI scans of brain, spinal cord and cauda equina, cerebrospinal fluid analysis and electrodiagnostic tests did not reveal any clinically significant abnormalities. A definitive final diagnosis was not reached in any of the cats, but hypersensitivity dermatitis was suspected in two cases. A variety of medications was used alone or in combination, including gabapentin (n = 6), meloxicam (n = 4), antibiotics (n = 4), phenobarbital (n = 2), prednisolone (n = 2) and topiramate (n = 2); ciclosporin, clomipramine, fluoxetine, amitriptyline and tramadol were used in one cat each. Clinical improvement was achieved in six cases; in five cats complete remission of clinical signs was achieved with gabapentin alone (n = 2), a combination of gabapentin/ciclosporin/amitriptyline (n = 1), gabapentin/prednisolone/phenobarbital (n = 1) or gabapentin/topiramate/meloxicam (n = 1).

RELEVANCE AND NOVEL INFORMATION

This is the first retrospective study on a series of cats with FHS. The diagnostic work-up did not reveal any significant abnormalities of the central or peripheral nervous system; dermatological and behavioural problems could not be ruled out. We propose an integrated multidisciplinary diagnostic pathway to be used for the management of clinical cases and for future prospective studies.

Use of Gabapentin in the Treatment of Substance Use and Psychiatric Disorders: A Systematic Review

Objective: Gabapentin (GBP) is an anticonvulsant medication that is also used to treat restless legs syndrome (RLS) and posttherapeutic neuralgia. GBP is commonly prescribed off-label for psychiatric disorders despite the lack of strong evidence. However, there is growing evidence that GBP may be effective and clinically beneficial in both psychiatric disorders and substance use disorders. This review aimed to perform a systematic analysis of peer-reviewed published literature on the efficacy of GBP in the treatment of psychiatric disorders and substance use disorders. Methods: This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The PubMed and Ovid MEDLINE literature databases were screened and filtered by using specific search terms and inclusion/exclusion criteria. The full texts of selected studies were subsequently retrieved and reviewed. The search terms generated 2,604 results from the databases. After excluding all duplicates, 1,088 citations were left. Thereafter, we applied inclusion and exclusion criteria; a total of 54 papers were retained for detailed review. Results: This literature review concludes that GBP appears to be effective in the treatment of various forms of anxiety disorders. It shows some effectiveness in bipolar disorder as an adjunctive therapeutic agent, while the evidence for monotherapy is inconclusive. In substance use disorders, GBP is effective for acute alcohol withdrawal syndrome (AWS) with mild to moderate severity; it reduces cravings, improves the rate of abstinence, and delays return to heavy drinking. GBP may have some therapeutic potential in the treatment of opioid addiction and cannabis dependence, but there is limited evidence to support its use. No significant benefit of GBP has been conclusively observed in the treatment of OCD, PTSD, depression, or cocaine and amphetamine abuse. Conclusion: GBP appears to be effective in some forms of anxiety disorders such as preoperative anxiety, anxiety in breast cancer survivors, and social phobia. GBP has shown to be safe and effective in the treatment of alcohol dependence. However, the literature suggests that GBP is effective as an adjunctive medication rather than a monotherapy. More clinical trials with larger patient populations are needed to support gabapentin's off-label use in psychiatric disorders and substance use disorders. It is worth noting that numerous clinical studies that are discussed in this review are open-label trials, which are inherently less rigorously analyzed. Therefore, more extensive investigations are required to examine not only the efficacy of GBP, but also its safety and tolerance.

Psychotropic Medication of Acute Episodes of Mood Disorders: Current Prescription Attitude in Two Psychiatric Wards in Cagliari, Italy

Background:

Medication of acute episodes of mood disorders has changed over the last decades following the results of randomized clinical trials.

Objective:

The aim of this study was to analyze medication prescribed at discharge from two psychiatric wards. We focused on hospitalization as one of the best opportunities to start prophylaxis.

Methods:

We examined retrospectively the clinical records of 357 patients hospitalized for mood episodes in two psychiatric wards in the Cagliari area (SPDC-1 and SPDC-2) between 1 January and 31 December 2016. We focused on the psychotropic medication prescribed at discharge from the hospital.

Results:

Most patients were discharged with antipsychotics (86%) and/or benzodiazepines (89%). Combined medication was frequent, including various co-administration of first-generation and/or second-generation antipsychotics (26% of patients), or antipsychotics combined with mood-stabilizers (51% of patients). There was a preferential prescription of first-generation antipsychotics in SPDC-1, and of second-generation antipsychotics in SPDC-2. Prescription of lithium was significantly more frequent in SPDC-1.

Conclusion:

Although the treatment was in line with randomized clinical trials, the choice of individual psychotropic agents differed significantly between the two wards. Different prescription attitudes can have consequences on the long-term outcome of patients discharged from the hospital after an acute mood episode.

The vicious cycle of itch and anxiety

Chronic itch is associated with increased stress, anxiety, and other mood disorders. In turn, stress and anxiety exacerbate itch, leading to a vicious cycle that affects patient behavior (scratching) and worsens disease prognosis and quality of life. This cycle persists across chronic itch conditions of different etiologies and even to some extent in healthy individuals, suggesting that the final common pathway for itch processing (the central nervous system) plays a major role in the relationship between itch and anxiety. Pharmacological and nonpharmacological treatments that reduce anxiety have shown promising anti-itch effects. Further research is needed to establish specific central mechanisms of the itch-anxiety cycle and provide new targets for treatment.

The Emerging Neurobiology of Bipolar Disorder

Bipolar disorder (BD) is a leading cause of global disability. Its biological basis is unknown, and its treatment unsatisfactory. Here, we review two recent areas of progress. First, the discovery of risk genes and their implications, with a focus on voltage-gated calcium channels as part of the disease process and as a drug target. Second, facilitated by new technologies, it is increasingly apparent that the bipolar phenotype is more complex and nuanced than simply one of recurring manic and depressive episodes. One such feature is persistent mood instability, and efforts are underway to understand its mechanisms and its therapeutic potential. BD illustrates how psychiatry is being transformed by contemporary neuroscience, genomics, and digital approaches.

Pharmacological challenge studies with acute psychosocial stress

Chronic stress is known to affect many psychiatric disorders, and studies of responses to acute stress may reveal processes that ultimately lead to maladaptive responses to chronic stress. Many studies have used simulated public speaking tasks to induce stress in the laboratory and, of interest to this review, the tasks have been used to assess the effects of both therapeutic and nonmedical drugs on stress reactivity. Here we review 38 studies that examined effects of single doses of drugs on subjective, cardiovascular and hormonal responses to an acute social stressor in healthy volunteers. Most studies have used the Trier Social Stress Test (TSST), or variations on it involving public speaking or mental arithmetic. Pharmacological studies with the TSST (ph-TSST) have been conducted for three main reasons: i) to determine the clinical effectiveness of psychiatric medications to reduce stress responses, ii) to investigate the neurochemical mechanisms involved in the stress response, and iii) to determine whether drugs of abuse relieve, or occasionally worsen, responses to acute stress. The review indicates that standard anxiolytic medications consistently reduce subjective responses to the TSST, whereas single doses of antidepressants produce mixed effects. Mechanistic studies indicate that several neurotransmitter systems are involved in the stress response, including serotonin, norepinephrine, GABA, glutamate, opioids, and endocannabinoids. Among drugs of abuse, alcohol and cannabinoids exert some stress-dampening effects, whereas caffeine, nicotine, and amphetamines tend to increase stress responses. Comparing outcome measures of the responses to stress, subjective ratings of anxiety are among the most sensitive indices of the stress response, with cortisol levels second and cardiovascular responses least sensitive. We conclude that the TSST is a valuable tool to study the clinical effectiveness of medications for stress-related disorders, and that it is important to use standardized procedures to enable comparisons across studies.

HCN Channel Targets for Novel Antidepressant Treatment

Major depressive disorder (MDD) is a chronic and potentially life threatening illness that carries a staggering global burden. Characterized by depressed mood, MDD is often difficult to diagnose and treat owing to heterogeneity of syndrome and complex etiology. Contemporary antidepressant treatments are based on improved monoamine-based formulations from serendipitous discoveries made > 60 years ago. Novel antidepressant treatments are necessary, as roughly half of patients using available antidepressants do not see long-term remission of depressive symptoms. Current development of treatment options focuses on generating efficacious antidepressants, identifying depression-related neural substrates, and better understanding the pathophysiological mechanisms of depression. Recent insight into the brain's mesocorticolimbic circuitry from animal models of depression underscores the importance of ionic mechanisms in neuronal homeostasis and dysregulation, and substantial evidence highlights a potential role for ion channels in mediating depression-related excitability changes. In particular, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are essential regulators of neuronal excitability. In this review, we describe seminal research on HCN channels in the prefrontal cortex and hippocampus in stress and depression-related behaviors, and highlight substantial evidence within the ventral tegmental area supporting the development of novel therapeutics targeting HCN channels in MDD. We argue that methods targeting the activity of reward-related brain areas have significant potential as superior treatments for depression.