Clinical trials of N-acetylcysteine in psychiatry and neurology: A systematic review

S-(N,N-diethyldithiocarbamoyl)-N-acetyl-l-cysteine for the treatment of non-small cell lung cancer through regulating NF-κB signalling pathway without neurotoxicity

The discovery of novel targeted agents for non-small cell lung cancer (NSCLC) remains an important research landscape due to the limited efficacy, side effects and drug resistance of current treatment options. Among many repurposed drugs, disulphiram (DSF) has shown the potential to target tumours. However, its unpleasant neurotoxicity greatly limits its use. A DSF derivative, S-(N,N-diethyldithiocarbamoyl)-N-acetyl-l-cysteine (DS-NAC), was synthesised against NSCLC. The therapeutic effects, mechanism and toxicities of DS-NAC were evaluated in A549 and H460 cells and the mouse model of in situ lung cancer. The in vitro results exhibited that DS-NAC had potent anti-proliferation, apoptotic, anti-metastasis and epithelial-mesenchymal transition (EMT) inhibition effects. In the orthotopic lung cancer mouse model, therapeutic effects of DS-NAC were better than those of DSF and were similar to docetaxel (DTX). Also, results from western blot and immunohistochemistry showed that DS-NAC in combination with copper exerted therapeutic effects via regulating NF-κB signalling pathway and ROS-related proteins such as HIF-1α, Nrf2 and PKC-δ rather than regulating ROS level directly. Moreover, the safety evaluation study showed that DS-NAC had low haematologic and hepatic toxicities in comparison with DTX as well as low neurological toxicity compared with DSF. DS-NAC could be a promising anti-lung cancer agent with a favourable safety profile.

Cellular and Molecular Mechanisms of Hypertrophy of Ligamentum Flavum

Hypertrophy of the ligamentum flavum (HLF) is a common contributor to lumbar spinal stenosis (LSS). Fibrosis is a core pathological factor of HLF resulting in degenerative LSS and associated low back pain. Although progress has been made in HLF research, the specific molecular mechanisms that promote HLF remain to be defined. The molecular factors involved in the onset of HLF include increases in inflammatory cytokines such as transforming growth factor (TGF)-β, matrix metalloproteinases, and pro-fibrotic growth factors. In this review, we discuss the current understanding of the mechanisms involved in HLF with a particular emphasis on aging and mechanical stress. We also discuss in detail how several pathomechanisms such as fibrosis, proliferation and apoptosis, macrophage infiltration, and autophagy, in addition to several molecular pathways involving TGF-β1, mitogen-activated protein kinase (MAPKs), and nuclear factor-κB (NF-κB) signaling, PI3K/AKT signaling, Wnt signaling, micro-RNAs, extracellular matrix proteins, reactive oxygen species (ROS), etc. are involved in fibrosis leading to HLF. We also present a summary of the current advancements in preclinical animal models for HLF research. In addition, we update the current and potential therapeutic targets/agents against HLF. An improved understanding of the molecular processes behind HLF and a novel animal model are key to developing effective LSS prevention and treatment strategies.

N-acetylcysteine Clinical Applications

This study aims to evaluate the therapeutic application of N-acetylcysteine (NAC) as a treatment or adjunct therapy for various medical conditions. While its efficacy in treating acetaminophen overdose, cystic fibrosis, and chronic obstructive pulmonary disease is well-established, emerging evidence suggests that NAC may also benefit a broader spectrum of illnesses due to its safety, simplicity, and affordability. A comprehensive review was conducted by searching PubMed, relevant books, and conference proceedings for publications discussing NAC about the specified health conditions. The clinically relevant data were analysed using the American Family Physician Evidence-Based Medicine Toolkit, following a standard integrated review methodology. NAC shows potential as an adjunctive treatment for a wide range of medical conditions, particularly chronic diseases. It may be beneficial for polycystic ovary syndrome, endometriosis, male infertility, cataracts, glaucoma, dry eye syndrome, parkinsonism, multiple sclerosis, Alzheimer's disease, stroke outcomes, non-acetaminophen-induced acute liver failure, Crohn's disease, ulcerative colitis, schizophrenia, bipolar disorder, and obsessive-compulsive disorder. Although evidence for some conditions is less robust, NAC's therapeutic potential warrants further investigation. Given the aging population and the decline in glutathione levels, the use of NAC should be considered across a variety of medical conditions. This paper suggests that NAC supplementation could play a significant role in reducing morbidity and mortality associated with numerous chronic diseases.

Artemisia Argyi essential oil ameliorates acetaminophen-induced hepatotoxicity via CYP2E1 and γ-glutamyl cycle reprogramming

BACKGROUND

The hepatotoxicity induced by acetaminophen (APAP), a commonly used antipyretic, analgesic and anti-inflammatory drug in clinical practice, has received accumulated attention. Artemisia argyi essential oil (AAEO), a volatile oil component extracted from traditional Chinese medicine Artemisia argyi H.Lév. & Vaniot, has great hepatoprotective effects. However, the potential role of AAEO in APAP-induced hepatotoxicity has not been characterized. The present study aimed to investigate the effects of AAEO on hepatic metabolic changes in mice exposed to APAP.

METHODS

In this study, 300.00 mg/kg acetaminophen was used to establish liver injury model in C57BL/6 J mice. Hepatoprotective effect of AAEO on APAP-induced hepatotoxicity in mice was investigated by detecting liver function enzymes and histopathological examination. Secondly, UPLC-MS/MS was used to analyze the to analyze the small molecule metabolites and metabolic pathways induced by AAEO treatment; In addition, the effect of AAEO on APAP-induced oxidative stress and inflammation were evaluated by detecting the levels of glutathione peroxidase 4, malondialdehyde, reactive oxygen species and inflammatory factors. Finally, the active components of AAEO were preliminarily screened by cellular assays. The hepatoprotective effect of AAEO against APAP-induced hepatotoxicity was examined through the Western blotting, after the CYP2E1 gene was knocked down in AML12 cells by siRNA transfection.

RESULTS

Compared with the APAP group, AAEO could reduce the abnormal increase in the levels of liver function enzymes caused by APAP. AAEO could enhance the antioxidant capacity by down-regulating the biosynthesis pathway of unsaturated fatty acids and promoting the activity of antioxidant enzymes SOD and CAT in liver tissue induced by APAP. Our study revealed that AAEO promoted GSH synthesis and covalently combined to form APAP-GSH conjugates to reduce the accumulation of APAP in liver tissue. In addition, the chemical constituents in AAEO were analyzed by GC-MS/MS, and it was determined to identify that dihydro-beta-ionone and (-)-verbenone in AAEO might have a significant protective effect on hepatocyte survival after APAP exposure. Further studies on the hepatoprotective mechanism of AAEO indicated that it might reduce the production of toxic metabolites by regulating CYP2E1 levels.

CONCLUSION

AAEO exerted hepatoprotective effects on acetaminophen-induced hepatotoxicity in mice via regulating the activity of CYP2E1 and regulating the γ-glutamyl cycle pathway.

Drugs with glutamate-based mechanisms of action in psychiatry

Psychopharmacotherapy of major psychiatric disorders is mostly based on drugs that modulate serotonergic, dopaminergic, or noradrenergic neurotransmission, either by inhibiting their reuptake or by acting as agonists or antagonists on specific monoamine receptors. The effectiveness of this approach is limited by a significant delay in the therapeutic mechanism and self-perpetuating growth of treatment resistance with a consecutive number of ineffective trials. A growing number of studies suggest that drugs targeting glutamate receptors offer an opportunity for rapid therapeutic effect that may overcome the limitations of monoaminergic drugs. In this article, we present a review of glutamate-modulating drugs, their mechanism of action, as well as preclinical and clinical studies of their efficacy in treating mental disorders. Observations of the rapid, robust, and long-lasting effects of ketamine and ketamine encourages further research on drugs targeting glutamatergic transmission. A growing number of studies support the use of memantine and minocycline in major depressive disorder and schizophrenia. Amantadine, zinc, and Crocus sativus extracts yield the potential to ameliorate depressive symptoms in patients with affective disorders. Drugs with mechanisms of action based on glutamate constitute a promising pharmacological group in the treatment of mental disorders that do not respond to standard methods of therapy. However, further research is needed on their efficacy, safety, dosage, interactions, and side effects, to determine their optimal clinical use.

Review: Neuroprotective Nanocarriers in Glaucoma

Glaucoma stands as a primary cause of irreversible blindness globally, characterized by the progressive dysfunction and loss of retinal ganglion cells (RGCs). While current treatments primarily focus on controlling intraocular pressure (IOP), many patients continue to experience vision loss. Therefore, the research focus has shifted to therapeutic targets aimed at preventing or delaying RGC death and optic nerve degeneration to slow or halt disease progression. Traditional ocular drug administration, such as eye drops or oral medications, face significant challenges due to the eye's unique structural and physiological barriers, which limit effective drug delivery. Invasive methods like intravitreal injections can cause side effects such as bleeding, inflammation, and infection, making non-invasive delivery methods with high bioavailability very desirable. Nanotechnology presents a promising approach to addressing these limitations in glaucoma treatment. This review summarizes current approaches involving neuroprotective drugs combined with nanocarriers, and their impact for future use.

Impact of the Acetyl Group on Cysteine: A Study of N-Acetyl-Cysteine through Rotational Spectroscopy

Herein, we report a spectroscopic study of N-acetyl-L-cysteine, an important antioxidant drug, using Fourier-transform microwave techniques and in isolated conditions. Two conformers are observed, where most stable structure adopts a cis disposition, and the second conformer has a lower abundance and adopts a trans disposition. The rotational constants and the barriers to methyl internal rotation are determined for each conformer, allowing a precise conformation identification. The results show that the cis form adopts an identical structure in the crystal, solution, and gas phases. Additionally, the structures are contrasted against those of cysteine.

Herbal and Non-Herbal Dietary Supplements for Psychiatric Indications: Considerations in Liver Transplantation

PURPOSE OF REVIEW

Traditional, complementary, and integrative medicine (TCIM) modalities are widely employed. However, TCIM, specifically herbal and non-herbal dietary supplements, can pose challenges in the context of organ transplantation. In this review, we discuss common supplements used for psychiatric purposes and highlight important considerations for candidates and recipients of liver transplants.

RECENT FINDINGS

Ashwagandha, kava kava, green tea extract, skullcap, turmeric, and valerian have known idiosyncratic hepatotoxic potential and may complicate the liver transplantation course. Multiple supplements reportedly carry a lower risk of hepatotoxicity, though evidence for widespread use in those at risk for or with hepatic impairment is limited. Psychiatrists caring for candidates and recipients of liver transplants must recognize that patients may find supplements helpful in alleviating psychiatric symptoms, despite an overall limited evidence base. Evaluating benefit versus risk ratios and reviewing drug-drug interactions is essential to promote transplant candidacy and mitigate the possibility of native or graft liver dysfunction.

Biomarkers of mitochondrial dysfunction in autism spectrum disorder: A systematic review and meta-analysis

Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting 1 in 36 children and is associated with physiological abnormalities, most notably mitochondrial dysfunction, at least in a subset of individuals. This systematic review and meta-analysis discovered 204 relevant articles which evaluated biomarkers of mitochondrial dysfunction in ASD individuals. Significant elevations (all p < 0.01) in the prevalence of lactate (17%), pyruvate (41%), alanine (15%) and creatine kinase (9%) were found in ASD. Individuals with ASD had significant differences (all p < 0.01) with moderate to large effect sizes (Cohen's d' ≥ 0.6) compared to controls in mean pyruvate, lactate-to-pyruvate ratio, ATP, and creatine kinase. Some studies found abnormal TCA cycle metabolites associated with ASD. Thirteen controlled studies reported mitochondrial DNA (mtDNA) deletions or variations in the ASD group in blood, peripheral blood mononuclear cells, lymphocytes, leucocytes, granulocytes, and brain. Meta-analyses discovered significant differences (p < 0.01) in copy number of mtDNA overall and in ND1, ND4 and CytB genes. Four studies linked specific mtDNA haplogroups to ASD. A series of studies found a subgroup of ASD with elevated mitochondrial respiration which was associated with increased sensitivity of the mitochondria to physiological stressors and neurodevelopmental regression. Lactate, pyruvate, lactate-to-pyruvate ratio, carnitine, and acyl-carnitines were associated with clinical features such as delays in language, social interaction, cognition, motor skills, and with repetitive behaviors and gastrointestinal symptoms, although not all studies found an association. Lactate, carnitine, acyl-carnitines, ATP, CoQ10, as well as mtDNA variants, heteroplasmy, haplogroups and copy number were associated with ASD severity. Variability was found across biomarker studies primarily due to differences in collection and processing techniques as well as the intrinsic heterogeneity of the ASD population. Several studies reported alterations in mitochondrial metabolism in mothers of children with ASD and in neonates who develop ASD. Treatments targeting mitochondria, particularly carnitine and ubiquinol, appear beneficial in ASD. The link between mitochondrial dysfunction in ASD and common physiological abnormalities in individuals with ASD including gastrointestinal disorders, oxidative stress, and immune dysfunction is outlined. Several subtypes of mitochondrial dysfunction in ASD are discussed, including one related to neurodevelopmental regression, another related to alterations in microbiome metabolites, and another related to elevations in acyl-carnitines. Mechanisms linking abnormal mitochondrial function with alterations in prenatal brain development and postnatal brain function are outlined. Given the multisystem complexity of some individuals with ASD, this review presents evidence for the mitochondria being central to ASD by contributing to abnormalities in brain development, cognition, and comorbidities such as immune and gastrointestinal dysfunction as well as neurodevelopmental regression. A diagnostic approach to identify mitochondrial dysfunction in ASD is outlined. From this evidence, it is clear that many individuals with ASD have alterations in mitochondrial function which may need to be addressed in order to achieve optimal clinical outcomes. The fact that alterations in mitochondrial metabolism may be found during pregnancy and early in the life of individuals who eventually develop ASD provides promise for early life predictive biomarkers of ASD. Further studies may improve the understanding of the role of the mitochondria in ASD by better defining subgroups and understanding the molecular mechanisms driving some of the unique changes found in mitochondrial function in those with ASD.

Review of Management Considerations for Excoriation Disorder in Older Adults

Excoriation disorder (ED) is defined as compulsive skin picking that results in skin damage and emotional distress. Optimal management of ED includes individualized treatment plans consisting of psychotherapies, behavioral and pharmacologic interventions. Compared with younger populations, older adults are at increased risk for poor outcomes, such as infection and hospitalization, and require unique management considerations. Risk factors that contribute to disease burden include age-related changes to the skin and underlying medical and psychiatric comorbidities. A literature review was conducted on ED yielding limited evidence exclusive to older adults. The authors suggest a therapeutic approach to ED in older adults based on available evidence and experience from inpatient and outpatient psychiatric settings. Finally, opportunities for future research are highlighted.

A disulfiram derivative against lung cancer via the Notch signaling pathway without neurotoxicity and hepatotoxicity

The exploration of novel anti-lung cancer small-molecule drugs is important for drug resistance and adverse effects of chemotherapeutic drugs in current clinics. Disulfiram (DSF), as an antidote, has been proven to have excellent antitumor effects in combination with copper (Cu). However, the risk for potential neurotoxicity and hepatotoxicity in clinical use, as well as its poor water solubility, limits its use. In this study, we identified a DSF derivative, S-(N,N-diethyldithiocarbamoyl)-N-acetyl-L-cysteine, which could greatly increase the water solubility by converting it to a calcium salt (DS-NAC). The anti-lung cancer pharmacodynamic studies in vitro of DS-NAC were evaluated and a mouse model of lung cancer in situ was established to explore the therapeutic effects of DS-NAC compared with DSF and oxaliplatin (OXA). The results demonstrated that DS-NAC combined with Cu had superior cytotoxicity to DSF and OXA in the CCK8 assay against lung cancer cells, and exhibited potent anti-metastatic, epithelial-mesenchymal transition inhibition. In addition, DS-NAC showed better antitumor effects than DSF and comparable effects to OXA in lung cancer in situ model. In terms of the antitumor mechanism, we discovered that DS-NAC in combination with Cu exerted a greater inhibitory effect on the Notch pathway than DSF, which may account for its excellent antitumor effects. Finally, we verified the safety of DS-NAC in vivo, showing lower hepatotoxicity and neurotoxicity compared with DSF and OXA. DS-NAC is a promising anti-lung cancer drug with a favorable safety profile.

Efficacy and acceptability of anti-inflammatory agents in major depressive disorder: a systematic review and meta-analysis

Background

Anti-inflammatory agents have emerged as a potential new therapy for major depressive disorder (MDD). In this meta-analysis, our aim was to evaluate the antidepressant effect of anti-inflammatory agents and compare their efficacy.

Methods

We conducted a comprehensive search across multiple databases, including PubMed, Embase, Web of Science, Cochrane Review, Cochrane Trial, and ClinicalTrials.gov, to identify eligible randomized clinical trials. The primary outcome measures of our meta-analysis were efficacy and acceptability, while the secondary outcome measures focused on remission rate and dropout rate due to adverse events. We used odds ratio (OR) and 95% confidence interval (95% CI) to present our results.

Results

A total of 48 studies were included in our analysis. In terms of efficacy, anti-inflammatory agents demonstrated a significant antidepressant effect compared to placebo (OR = 2.04, 95% CI: 1.41-2.97, p = 0.0002). Subgroup analyses revealed that anti-inflammatory agents also exhibited significant antidepressant effects in the adjunctive therapy subgroup (OR = 2.17, 95% CI: 1.39-3.37, p = 0.0006) and in MDD patients without treatment-resistant depression subgroup (OR = 2.33, 95% CI: 1.53-3.54, p < 0.0001). Based on the surface under the cumulative ranking curve (SUCRA) value of network meta-analysis, nonsteroidal anti-inflammatory drugs (NSAIDs) (SUCRA value = 81.6) demonstrated the highest acceptability among the included anti-inflammatory agents.

Conclusion

In summary, our meta-analysis demonstrates that anti-inflammatory agents have significant antidepressant effects and are well-accepted. Furthermore, adjunctive therapy with anti-inflammatory agents proved effective in treating MDD. Among the evaluated anti-inflammatory agents, NSAIDs exhibited the highest acceptability, although its efficacy is comparable to placebo.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=422004), identifier CRD42023422004.

Dissecting hair breakage in alopecia areata: the central role of dysregulated cysteine homeostasis

In the initial stages of Alopecia Areata (AA), the predominance of hair breakage or exclamation mark hairs serves as vital indicators of disease activity. These signs are non-invasive and are commonly employed in dermatoscopic examinations. Despite their clinical salience, the underlying etiology precipitating this hair breakage remains largely uncharted territory. Our exhaustive review of the existing literature points to a pivotal role for cysteine-a key amino acid central to hair growth-in these mechanisms. This review will probe and deliberate upon the implications of aberrant cysteine metabolism in the pathogenesis of AA. It will examine the potential intersections of cysteine metabolism with autophagy, ferroptosis, immunity, and psychiatric manifestations associated with AA. Such exploration could illuminate new facets of the disease's pathophysiology, potentially paving the way for innovative therapeutic strategies.

L-Carnitine in the Treatment of Psychiatric and Neurological Manifestations: A Systematic Review

OBJECTIVE

L-carnitine (LC), a vital nutritional supplement, plays a crucial role in myocardial health and exhibits significant cardioprotective effects. LC, being the principal constituent of clinical-grade supplements, finds extensive application in the recovery and treatment of diverse cardiovascular and cerebrovascular disorders. However, controversies persist regarding the utilization of LC in nervous system diseases, with varying effects observed across numerous mental and neurological disorders. This article primarily aims to gather and analyze database information to comprehensively summarize the therapeutic potential of LC in patients suffering from nervous system diseases while providing valuable references for further research.

METHODS

A comprehensive search was conducted in PubMed, Web Of Science, Embase, Ovid Medline, Cochrane Library and Clinicaltrials.gov databases. The literature pertaining to the impact of LC supplementation on neurological or psychiatric disorders in patients was reviewed up until November 2023. No language or temporal restrictions were imposed on the search.

RESULTS

A total of 1479 articles were retrieved, and after the removal of duplicates through both automated and manual exclusion processes, 962 articles remained. Subsequently, a meticulous re-screening led to the identification of 60 relevant articles. Among these, there were 12 publications focusing on hepatic encephalopathy (HE), while neurodegenerative diseases (NDs) and peripheral nervous system diseases (PNSDs) were represented by 9 and 6 articles, respectively. Additionally, stroke was addressed in five publications, whereas Raynaud's syndrome (RS) and cognitive disorder (CD) each had three dedicated studies. Furthermore, migraine, depression, and amyotrophic lateral sclerosis (ALS) each accounted for two publications. Lastly, one article was found for other symptoms under investigation.

CONCLUSION

In summary, LC has demonstrated favorable therapeutic effects in the management of HE, Alzheimer's disease (AD), carpal tunnel syndrome (CTS), CD, migraine, neurofibromatosis (NF), PNSDs, RS, and stroke. However, its efficacy appears to be relatively limited in conditions such as ALS, ataxia, attention deficit hyperactivity disorder (ADHD), depression, chronic fatigue syndrome (CFS), Down syndrome (DS), and sciatica.

n-Acetylcysteine protects against diazinon-induced histopathological damage and apoptosis in renal tissue of rats

Diazinon (DZN) is a member of organophosphorus insecticides that has cytotoxic effects on different organs. n-Acetyl cysteine (NAC) is a widely used antioxidant in clinical, in vivo and in vitro studies. We evaluated the protective role of NAC against DZN-induced toxicity in kidney tissue of Wistar rats. 30 male Wistar rats were divided into 5 groups of control, single dose of DZN, continuous dose of DZN, single doses of DZN + NAC and continuous doses of DZN + NAC. Kidney function test (blood urea nitrogen, creatinine and uric acid) was provided. Levels of malondialdehyde (MDA), total antioxidant capacity (TAC) and total sulfhydryl (T-SH) were determined in renal tissues. Renal cells apoptosis was detected using TUNEL assay. The mRNA expressions of apoptosis, oxidative stress and inflammatory mediators, including B-cell lymphoma-2 (Bcl2), Bcl-2-associated X protein (Bax), superoxide dismutase (SOD), catalase (CAT), Interleukin 10 (IL-10), Tumor necrosis factor-α (TNF-α), Caspase-3 and Caspase-8 were analyzed in kidney tissues using Real Time PCR method. Chronic exposure to DZN was associated with severe morphological changes in the kidney, as well as impairment of its function and decreased kidney weights. Continues treatment with DZN significantly decreased the percentage of renal apoptotic cells as compared to rats treated with continuous dose of DZN alone (17.69 ± 3.67% vs. 39.46% ± 2.44%; p < 0.001). Continuous exposure to DZN significantly decreased TAC and T-SH contents, as well as SOD and CAT expression, but increased MDA contents in the kidney tissues (p < 0.001). A significant increase was observed in mRNA expression of Bax, Caspase-3, Caspase-8, as well as TNF-α following exposure to DZN, but the expression of IL-10 and Bcl2 was significantly decreased. NAC can protect kidney tissue against DZN-induced toxicity by elevating antioxidants capacity, mitigating oxidative stress, inflammation and apoptosis.

Pharmacological management of gambling disorder: an update of the literature

INTRODUCTION

Gambling disorder (GD) is a mental health condition characterized by persistent and problematic betting behavior. GD generates distress and impairment, and treatment options include psychological and pharmacological interventions.

AREAS COVERED

This narrative review explores existing pharmacological treatments for GD. The following classes of medications were considered: opioid-receptor antagonists (e.g. naltrexone and nalmefene), serotonin reuptake inhibitors (e.g. fluvoxamine, paroxetine, sertraline, escitalopram, and citalopram), glutamatergic agents (e.g. N-acetylcysteine (NAC), acamprosate, and memantine), mood stabilizers (e.g. topiramate, carbamazepine, lithium), and other medications (e.g. modafinil, nefazodone, olanzapine, haloperidol, tolcapone, and bupropion).

EXPERT OPINION

Due to the limitations of the studies reviewed, solid conclusions regarding the optimal choice of pharmacotherapy for individuals with GD are challenging to draw at this time. Despite some medications, such as naltrexone and nalmefene, showing promising results, efficacy has varied across studies. The review highlights current gaps/limitations, including small sample sizes, limited diversity in participant demographics, the need for exploring different gambling subtypes and treatment responses, high placebo response rates, lack of longer-term longitudinal information, limited investigation of neurobiological correlates and co-occurring disorders, and the importance of implementation research. Further research is needed to address these gaps and explore additional medications, as well as interventions like neuromodulation.

Efficacy of antioxidant supplementation in improving endocrine, hormonal, inflammatory, and metabolic statuses of PCOS: a meta-analysis and systematic review

Background and aim: A large number of recent studies have reported on the use of antioxidants in patients with polycystic ovary syndrome (PCOS). This study aimed to evaluate the antioxidant effects on PCOS. Methods: We searched PubMed, Embase, Web of Science, and The Cochrane Library to identify randomized controlled trials investigating the use of antioxidants in treating PCOS. Statistical analysis was performed using Review Manager 5.4. Stata17.0 software was used to conduct sensitivity analyses. Results: This meta-analysis included 49 articles and 62 studies. The sample comprised 1657 patients with PCOS from the antioxidant group and 1619 with PCOS from the placebo group. The meta-analysis revealed that the fasting blood glucose levels [standardized mean difference (SMD): -0.31, 95% confidence interval (CI): -0.39 to -0.22, P < 0.00001], the homeostatic model assessment of insulin resistance (SMD: -0.68, 95% CI: -0.87 to -0.50], P < 0.00001), and insulin levels (SMD: -0.68, 95% CI: -0.79 to -0.58, P < 0.00001) were significantly lower in patients with PCOS taking antioxidants than those in the placebo group. Further, total cholesterol levels (SMD: -0.38, 95% CI: -0.56 to -0.20, P < 0.001), low-density lipoprotein cholesterol levels (SMD: -0.24, 95% CI: -0.37 to -0.10, P = 0.0008), and very low-density lipoprotein levels (SMD: -0.53, 95% CI: -0.65 to -0.41, P < 0.00001) were lower in patients with PCOS taking antioxidant supplements compared with the placebo group. Total testosterone (TT) level (SMD: -0.78, 95% CI: -1.15 to -0.42, P < 0.0001), dehydroepiandrosterone level (SMD: -0.42, 95% CI: -0.58 to -0.25, P < 0.00001), and mean standard deviation modified Ferriman-Gallway (MF-G scores) (SMD: -0.63, 95% CI: -0.98 to -0.28, P = 0.0004) were lower in patients taking antioxidant supplements. C-reactive protein (CRP) levels (SMD: -0.48, 95% CI: -0.63 to -0.34, P < 0.000001), body mass index [mean difference (MD): -0.27, 95% CI: -0.50 to -0.03, P = 0.03], weight (MD: -0.73, 95% CI: -1.35 to -0.11, P = 0.02), and diastolic blood pressure (MD: -3.78, 95% CI: -6.30 to -1.26, P = 0.003) were significantly lower. Moreover, the levels of sex hormone-binding protein (SMD: 0.23, 95% CI: 0.07-0.38, P = 0.004), high-density lipoprotein cholesterol (SMD: 0.11, 95% CI: 0.01-0.20, P = 0.03), total antioxidant capacity (SMD: 0.59, 95% CI: 0.31-0.87, P < 0.0001), and quantitative insulin sensitivity index (SMD: 0.01, 95% CI: 0.01-0.02, P < 0.00001) were higher in patients with PCOS who took antioxidant supplements compared with the placebo group. Antioxidant supplements did not affect other analyzed parameters in these patients, including follicle-stimulating hormone, free androgen index, nitric oxide, glutathione, malondialdehyde, and diastolic blood pressure. Conclusions: Antioxidants are beneficial in treating PCOS. Our study might provide a new treatment strategy for patients with clinical PCOS. We hope that more high-quality studies evaluating the effects of antioxidants on patients with PCOS will be conducted in the future. Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023448088.

The Role of Twice-Daily N-acetylcysteine (NAC) 2400 mg in Smoking Cessation: A Randomized, Placebo-Controlled Trial in Indonesia

INTRODUCTION

 Tobacco smoking remains a health concern, especially in developing countries. Nicotine is significantly linked to many cancers and even second-hand exposure. Hence, smoking can increase the risk of lung and heart disease. This makes quitting smoking important and challenging. Success tends to rise by achieving abstinence with assisted pharmacology. These treatments aim to reduce symptoms of nicotine withdrawal. This is a preclinical trial on glutamate modulator in N-acetylcysteine (NAC) as a new potential treatment for smoking cessation. It is based on the administration of NAC related to elevated levels of dopamine in the central nervous system to accomplish successful smoking cessation.

AIM

This study evaluated the efficacy and tolerability of NAC for smoking cessation. The primary outcome was abstinence rate and the secondary outcomes of the study were to assess carbon monoxide exhalation value (COexh), the withdrawal symptoms, craving score, safety, and tolerability associated with the administration of NAC.

METHODS

This is a randomized clinical trial. Eligible smokers were treated with NAC 2400 mg twice daily (BID) or placebo to obtain a potential effective abstinence rate. Subjects recruited from the smoking cessation clinic were screened for eligibility and were randomized to either the NAC or placebo group. The trial consisted of a four-week treatment phase and participants were evaluated each week with a brief counseling. Intention to treat data analysis was performed from 2018 to 2019. Smoking cessation status was verified by measuring the amount of carbon monoxide exhaled and by documenting their smoking habits. Adverse events (AEs) have also been observed on each visit.

RESULTS

A total of 90 male smokers with a mean (SD) age of 38.7 (11) years were randomized into two groups to receive NAC (n=45) and placebo (n=45). The primary outcome revealed that the abstinence rate was significantly higher for the NAC group than the placebo group (37.7% vs 6.6%; p=0.02). These findings were supported by data comparison between the NAC group and placebo group of COexh (ppm) (9.59 ±7.4 vs 13,4 ±6.1; p=0.04) and cigarette consumption/week (10 vs 46; p <0.001), which were statistically significant. Comparison of withdrawal with the Minnesota Nicotine Withdrawal Score between the NAC group and the placebo group showed lower values (8 (1-31) vs 11 (0-43); p=0.178), respectively, even though not statistically significant. Compared to the placebo group, the craving score (6 (2-29) vs 12 (6-31); p=0.04) in the NAC group was significantly lower. The most common adverse event was mild gastrointestinal effects (28.9%) and arthralgia (2.2%). No serious adverse events were detected.

CONCLUSIONS

 Despite a small sample size, the data demonstrate the potential benefits of NAC that may help elevate abstinence rates and promote successful smoking cessation pharmacotherapy. Comprehensive treatment combining pharmacologic therapy and counseling increases smoking cessation success rates. It is essential to conduct a randomized multicenter study with a large population to support a sustained abstinence rate using NAC.

N-acetyl Cysteine Supplementation to Alleviate Skin Picking Disorder: A Case Report

There are body-focused repetitive behaviors, such as skin picking, trichotillomania, or nail biting, for which therapeutic interventions are available and can be tried, but unfortunately, there are no FDA-approved medications specifically for them. These disorders can cause functional impairment, disrupt activities of daily living, and be burdensome for both the patients and their loved ones. This case report will discuss an over-the-counter vitamin supplement, N-acetyl cysteine (NAC), that can be used safely but is often overlooked.

N-Acetylcysteine and a Specialized Preventive Intervention for Individuals at High Risk for Psychosis: A Randomized Double-Blind Multicenter Trial

Background and Hypothesis

Clinical high risk for psychosis (CHR-P) offers a window of opportunity for early intervention and recent trials have shown promising results for the use of N-acetylcysteine (NAC) in schizophrenia. Moreover, integrated preventive psychological intervention (IPPI), applies social-cognitive remediation to aid in preventing the transition to the psychosis of CHR-P patients.

Study Design

In this double-blind, randomized, controlled multicenter trial, a 2 × 2 factorial design was applied to investigate the effects of NAC compared to placebo (PLC) and IPPI compared to psychological stress management (PSM). The primary endpoint was the transition to psychosis or deterioration of CHR-P symptoms after 18 months.

Study Results

While insufficient recruitment led to early trial termination, a total of 48 participants were included in the study. Patients receiving NAC showed numerically higher estimates of event-free survival probability (IPPI + NAC: 72.7 ± 13.4%, PSM + NAC: 72.7 ± 13.4%) as compared to patients receiving PLC (IPPI + PLC: 56.1 ± 15.3%, PSM + PLC: 39.0 ± 17.4%). However, a log-rank chi-square test in Kaplan-Meier analysis revealed no significant difference of survival probability for NAC vs control (point hazard ratio: 0.879, 95% CI 0.281-2.756) or IPPI vs control (point hazard ratio: 0.827, 95% CI 0.295-2.314). The number of adverse events (AE) did not differ significantly between the four groups.

Conclusions

The superiority of NAC or IPPI in preventing psychosis in patients with CHR-P compared to controls could not be statistically validated in this trial. However, results indicate a consistent pattern that warrants further testing of NAC as a promising and well-tolerated intervention for CHR patients in future trials with adequate statistical power.

N-Acetylcysteine and Atherosclerosis: Promises and Challenges

Atherosclerosis remains a leading cause of cardiovascular diseases. Although the mechanism for atherosclerosis is complex and has not been fully understood, inflammation and oxidative stress play a critical role in the development and progression of atherosclerosis. N-acetylcysteine (NAC) has been used as a mucolytic agent and an antidote for acetaminophen overdose with a well-established safety profile. NAC has antioxidant and anti-inflammatory effects through multiple mechanisms, including an increase in the intracellular glutathione level and an attenuation of the nuclear factor kappa-B mediated production of inflammatory cytokines like tumor necrosis factor-alpha and interleukins. Numerous animal studies have demonstrated that NAC significantly decreases the development and progression of atherosclerosis. However, the data on the outcomes of clinical studies in patients with atherosclerosis have been limited and inconsistent. The purpose of this review is to summarize the data on the effect of NAC on atherosclerosis from both pre-clinical and clinical studies and discuss the potential mechanisms of action of NAC on atherosclerosis, as well as challenges in the field.

An Open-Label Case Series of Glutathione Use for Symptomatic Management in Children with Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a type of neurodevelopmental disorder that has been diagnosed in an increasing number of children around the world. The existing data suggest that early diagnosis and intervention can improve ASD outcomes. The causes of ASD remain complex and unclear, and there are currently no clinical biomarkers for autism spectrum disorder. There is an increasing recognition that ASD might be associated with oxidative stress through several mechanisms including abnormal metabolism (lipid peroxidation) and the toxic buildup of reactive oxygen species (ROS). Glutathione acts as an antioxidant, a free radical scavenger and a detoxifying agent. This open-label pilot study investigates the tolerability and effectiveness of oral supplementation with OpitacTM gluthathione as a treatment for patients with ASD. The various aspects of glutathione OpitacTM glutathione bioavailability were examined when administered by oral routes. The absorption of glutathione from the gastrointestinal tract has been recently investigated. The results of this case series suggest that oral glutathione supplementation may improve oxidative markers, but this does not necessarily translate to the observed clinical improvement of subjects with ASD. The study reports a good safety profile of glutathione use, with stomach upset reported in four out of six subjects. This article discusses the role of the gut microbiome and redox balance in ASD and notes that a high baseline oxidative burden may make some patients poor responders to glutathione supplementation. In conclusion, an imbalance in redox reactions is only one of the many factors contributing to ASD, and further studies are necessary to investigate other factors, such as impaired neurotransmission, immune dysregulation in the brain, and mitochondrial dysfunction.

Acetylcysteine increases sensitivity of ceftazidime-avibactam-resistant enterobacterales with different enzymatic resistance to ceftazidime-avibactam in vitro and in vivo

BACKGROUND

Ceftazidime-avibactam (CZA) improves treatment outcomes for infections caused by carbapenem-resistant organisms, but has led to serious bacterial resistance. Acetylcysteine (NAC) is an approved medication that protects the respiratory tract through antioxidant and anti-inflammatory effects.

RESULTS

This study found that NAC combined with CZA effectively inhibits the growth of CZA-resistant clinical Enterobacterales strains. The CZA/NAC combination inhibits biofilm formation in vitro and decreases bacterial burden in a mouse thigh infection model. The combination is biocompatible and primarily increases cell membrane permeability to cause bacterial death.

CONCLUSIONS

These findings prove that the CZA/NAC combination has potential as a treatment for CZA-resistant Enterobacterales infections.

Antagonistic effects of N-acetylcysteine on lead-induced apoptosis and oxidative stress in chicken embryo fibroblast cells

Lead (Pb) is a heavy metal that can have harmful effects on the environment, which has severe cytotoxicity in many animal tissues. N-acetylcysteine (NAC) has antioxidant activity, reducing lead-induced oxidative stress and apoptosis, but its role in chicken cells is unknown. The current study explored the antagonistic effect of NAC on lead-induced apoptosis and oxidative stress in chicken embryo fibroblast (CEF). In this study, CEF was used as a model to measure the cytotoxic effects of lead nitrate at different concentrations, demonstrating a dose-dependent effect on CEF activity. Employing inverted microscopy, the investigation of morphological alterations in CEF cells was conducted. Fluorescence staining methodology enabled the assessment of reactive oxygen species (ROS) levels within CEF cells. Moreover, an enzyme-linked immunosorbent assay was utilized to detect the presence of oxidative damage indicators encompassing superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) activity, malondialdehyde (MDA) content, and total antioxidant capacity (T-AOC) within CEF cells. Furthermore, the determination of the apoptosis rate of CEF cells was accomplished through the utilization of the Hoechst 33258 staining method in combination with the Annexin V-FITC dual staining method. By using RT-qPCR for detection, lead treatment increased expression of pro-apoptotic genes, caspase-3, and caspase-9, and reduced expression of anti-apoptotic genes, Bcl-2, and BI-1. Reduced antioxidant capacity was shown by increased ROS and MDA levels in CEF cells after lead treatment. The results showed that NAC inhibited the expression of caspase-3 and caspase-9 in lead-treated CEF cells, while NAC had a certain inhibitory effect on the relative expression of Bcl-2 and BI-1 mRNA in lead-induced CEF cells. NAC significantly reduced lead-induced oxidative damage and apoptosis. Overall, our results demonstrate a novel protective effect of NAC against lead-induced injury in chicken cells, providing a theoretical basis for future investigations of drugs that are effective in preventing lead poisoning in animals.

Cerebral venous congestion alters brain metabolite profiles, impairing cognitive function

Vascular cognitive impairment (VCI) represents the second most common cause of dementia after Alzheimer's disease, and pathological changes in cerebral vascular structure and function are pivotal causes of VCI. Cognitive impairment caused by arterial ischemia has been extensively studied the whole time; the influence of cerebral venous congestion on cognitive impairment draws doctors' attention in recent clinical practice, but the underlying neuropathophysiological alterations are not completely understood. This study elucidated the specific pathogenetic role of cerebral venous congestion in cognitive-behavioral deterioration and possible electrophysiological mechanisms. Using cerebral venous congestion rat models, we found these rats exhibited decreased long-term potentiation (LTP) in the hippocampal dentate gyrus and impaired spatial learning and memory. Based on untargeted metabolomics, N-acetyl-L-cysteine (NAC) deficiency was detected in cerebral venous congestion rats; supplementation with NAC appeared to ameliorate synaptic deficits, rescue impaired LTP, and mitigate cognitive impairment. In a cohort of cerebral venous congestion patients, NAC levels were decreased; NAC concentration was negatively correlated with subjective cognitive decline (SCD) score but positively correlated with mini-mental state examination (MMSE) score. These findings provide a new perspective on cognitive impairment and support further exploration of NAC as a therapeutic target for the prevention and treatment of VCI.

Taurine and N-acetylcysteine treatments prevent memory impairment and metabolite profile alterations in the hippocampus of high-fat diet-fed female mice

Background: Obesity constitutes a risk factor for cognitive impairment. In rodent models, long-term exposure to obesogenic diets leads to hippocampal taurine accumulation. Since taurine has putative cyto-protective effects, hippocampal taurine accumulation in obese and diabetic models might constitute a counteracting response to metabolic stress. Objective: We tested the hypothesis that treatment with taurine or with N-acetylcysteine (NAC), which provides cysteine for the synthesis of taurine and glutathione, prevent high-fat diet (HFD)-associated hippocampal alterations and memory impairment. Methods: Female mice were fed either a regular diet or HFD. Some mice had access to 3%(w/v) taurine or 3%(w/v) NAC in the drinking water. After 2 months, magnetic resonance spectroscopy (MRS) was used to measure metabolite profiles. Memory was assessed in novel object and novel location recognition tests. Results: HFD feeding caused memory impairment in both tests, and reduced concentration of lactate, phosphocreatine-to-creatine ratio, and the neuronal marker N-acetylaspartate in the hippocampus. Taurine and NAC prevented HFD-induced memory impairment and N-acetylaspartate reduction. NAC, but not taurine, prevented the reduction of lactate and phosphocreatine-to-creatine ratio. MRS revealed NAC/taurine-induced increase of hippocampal glutamate and GABA levels. Conclusion: NAC and taurine can prevent memory impairment, while only NAC prevents alterations of metabolite concentrations in HFD-exposed female mice.

N-Acetylcysteine and Probenecid Adjuvant Therapy for Traumatic Brain Injury

N-Acetylcysteine (NAC) has shown promise as a putative neurotherapeutic for traumatic brain injury (TBI). Yet, many such promising compounds have limited ability to cross the blood-brain barrier (BBB), achieve therapeutic concentrations in brain, demonstrate target engagement, among other things, that have hampered successful translation. A pharmacologic strategy for overcoming poor BBB permeability and/or efflux out of the brain of organic acid-based, small molecule therapeutics such as NAC is co-administration with a targeted or nonselective membrane transporter inhibitor. Probenecid is a classic ATP-binding cassette and solute carrier inhibitor that blocks transport of organic acids, including NAC. Accordingly, combination therapy using probenecid as an adjuvant with NAC represents a logical neurotherapeutic strategy for treatment of TBI (and other CNS diseases). We have completed a proof-of-concept pilot study using this drug combination in children with severe TBI-the Pro-NAC Trial (ClinicalTrials.gov NCT01322009). In this review, we will discuss the background and rationale for combination therapy with probenecid and NAC in TBI, providing justification for further clinical investigation.

Advancing the preclinical study of comorbid neuroHIV and substance use disorders: Current perspectives and future directions

Human immunodeficiency virus (HIV) remains a persistent public health concern throughout the world. Substance use disorders (SUDs) are a common comorbidity that can worsen treatment outcomes for people living with HIV. The relationship between HIV infection and SUD outcomes is likely bidirectional, making clear interrogation of neurobehavioral outcomes challenging in clinical populations. Importantly, the mechanisms through which HIV and addictive drugs disrupt homeostatic immune and CNS function appear to be highly overlapping and synergistic within HIV-susceptible reward and motivation circuitry in the central nervous system. Decades of animal research have revealed invaluable insights into mechanisms underlying the pathophysiology SUDs and HIV, although translational studies examining comorbid SUDs and HIV are very limited due to the technical challenges of modeling HIV infection preclinically. In this review, we discuss preclinical animal models of HIV and highlight key pathophysiological characteristics of each model, with a particular emphasis on rodent models of HIV. We then review the implementation of these models in preclinical SUD research and identify key gaps in knowledge in the field. Finally, we discuss how cutting-edge behavioral neuroscience tools, which have revealed key insights into the neurobehavioral mechanisms of SUDs, can be applied to preclinical animal models of HIV to reveal potential, novel treatment avenues for comorbid HIV and SUDs. Here, we argue that future preclinical SUD research would benefit from incorporating comorbidities such as HIV into animal models and would facilitate the discovery of more refined, subpopulation-specific mechanisms and effective SUD prevention and treatment targets.

Novel pharmacotherapy targeting the positive symptoms of schizophrenia

INTRODUCTION

The severity of positive symptoms in schizophrenia is associated with poor prognosis. About one-third of schizophrenia patients partially respond to treatment with available antipsychotics. The purpose of the present manuscript is to provide an updated overview of novel pharmacotherapy targeting positive symptoms in schizophrenia.

AREAS COVERED

A comprehensive research on the main database sources (PubMed, PsychINFO, Isi Web of Knowledge, MEDLINE, and EMBASE) was performed to obtain original articles published till 31st January 2023 about new pharmacological strategies for the treatment of positive symptoms in schizophrenia.

EXPERT OPINION

The most promising compounds include: lamotrigine, pro-cognitive-compounds (donepezil - in the short term, idazoxan and piracetam) and drugs acting partially or totally outside the Central Nervous System (CNS) (anti-inflammatory drugs: celecoxib, methotrexate; cardiovascular compounds: L-theanine, mononitrate isosorbide, propentofylline, sodium nitroprusside; metabolic regulators: diazoxide, allopurinol; others: bexarotene, raloxifene [in women]). The effectiveness of the latter compounds indicates that other biological systems, such as immunity or metabolism can be object of future research to identify pharmacological targets for positive symptoms of schizophrenia. Mirtazapine could be useful for treating negative symptoms without increasing the risk of a worsening of delusions/hallucinations. Nevertheless, the lack of replication of studies prevents to draw definitive conclusions and future studies are needed to confirm the findings presented in this overview.

A multi-centre, double-blind, 12-week, randomized, placebo-controlled trial of adjunctive N-Acetylcysteine for treatment-resistant PTSD

BACKGROUND

PTSD may involve oxidative stress, and N-acetylcysteine (NAC) may reduce the impact of oxidative stress in the brain. This study aims to investigate the efficacy of adjuvant NAC in people with treatment-resistant PTSD.

METHODS

A multicentre, randomised, double-blind, placebo-controlled trial for adults with PTSD unresponsive to first-line treatment. The intervention was either oral NAC 2.7 g/day or placebo for 12 weeks. The primary outcome was change in Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) at 12 weeks compared with baseline. Secondary outcomes included depression and substance craving. Follow-up measures were obtained at 16 and 64-weeks.

RESULTS

133 patients were assessed, with 105 randomised; 81 participants completed the 12-week trial, 79 completed week-16 follow-up, and 21 completed week-64 follow-up. There were no significant differences between those taking NAC and those taking placebo in CAPS-5 scores at week 12, nor in secondary outcomes. Significant between-group differences were observed at week 64 in craving duration (Cohen's d = 1.61) and craving resistance (Cohen's d = 1.03), both in favour of NAC.

CONCLUSION

This was the first multicentre, double-blind, randomised, placebo-controlled trial of adjunctive NAC for treatment-resistant PTSD. No benefit of NAC was observed in this group beyond that provided by placebo at end of the trial.

TRIAL REGISTRATION

ACTRN12618001784202, retrospectively registered 31/10/2018, URL: http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376004.

Ticlopidine induces embryonic development toxicity and hepatotoxicity in zebrafish by upregulating the oxidative stress signaling pathway

Ticlopidine exerts its anti-platelet effects mainly by antagonizing platelet p2y12 receptors. Previously, a few studies have shown that ticlopidine can induce liver injury, but the exact mechanism of hepatotoxicity remains unclear. Oxidative stress, metabolic disorders, hepatocyte apoptosis, lipid peroxidation, and inflammatory responses can all lead to hepatic liver damage, which can cause hepatotoxicity. In this study, in order to deeply explore the potential molecular mechanisms of ticlopidine -induced hepatotoxicity, we used zebrafish as a model organism to comprehensively evaluate the hepatotoxicity of ticlopidine and its associated mechanism. Three days post-fertilization, zebrafish larvae were exposed to varying concentrations (1.5, 1.75 and 2 μg/mL) of ticlopidine for 72 h, in contrast, adult zebrafish were exposed exposure to 4 μg/mL of ticlopidine for 28 days. Ticlopidine-exposed zebrafish larvae showed changes in liver morphology, shortened body length, and delayed development of the swim bladder development. Liver tissues of ticlopidine-exposed zebrafish larvae and adults stained with Hematoxylin & Eosin revealed vacuolization and increased cellular interstitial spaces in liver tissues. Furthermore, using Oil Red O and periodic acid-Schiff staining methods and evaluating different metabolic enzymes of ticlopidine-exposed zebrafish larvae and adults suggested abnormal liver metabolism and liver injury in both ticlopidine-exposed zebrafish larvae and adults. Ticlopidine also significantly elevated inflammation and oxidative stress and reduced hepatocyte proliferation. During the rescue intervention using N-acetylcysteine, we observed significant improvement in ticlopidine-induced morphological changes in the liver, shortened body length, delayed swim bladder development, and proliferation of liver tissues showed significant improvement. In conclusion, ticlopidine might inhibit normal development and liver proliferation in zebrafish by upregulation of oxidative stress levels, thus leading to embryonic developmental toxicity and hepatotoxicity. In this study, we used zebrafish as a model organism to elucidate the developmental toxicity and hepatotoxicity induced by ticlopidine upregulation of oxidative stress signaling pathway in zebrafish, providing a theoretical basis for clinical application.

Post-inflammatory administration of N-acetylcysteine reduces inflammation and alters receptor levels in a cellular model of Parkinson's disease

Parkinson's disease (PD) is a complex, multifactorial neurodegenerative disease with a prevalence of 1% over the age of 55. Neuropathological hallmarks of PD include the loss of dopaminergic neurons in the substantia nigra pars compacta and the accumulation of Lewy bodies that contain a variety of proteins and lipids including alpha-synuclein (α-syn). Although the formation of α-syn occurs intracellularly, it can also be found in the extracellular space where it can be taken up by neighboring cells. Toll-like receptor 2 (TLR2) is an immune system receptor that has been shown to recognize extracellular α-syn and modulate its uptake by other cells. Lymphocyte-activation gene 3 (LAG3), an immune checkpoint receptor, has also been proposed to play a role in extracellular α-syn internalization; however, a recent study has disputed this role. Internalized α-syn can trigger expression and secretion of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, IL-2, and IL-6 and induce neuroinflammation, apoptosis, and mitophagy that results in cellular death. In this study, we tested if N-acetylcysteine (NAC), an anti-inflammatory and anti-carcinogenic drug, can circumvent the detrimental effects of neuroinflammation and induce an anti-inflammatory response by modulating transcription and expression of TLR2 and LAG3 receptors. Cells overexpressing wild-type α-syn were treated with TNF-α to induce inflammation followed by NAC to inhibit the deleterious effects of TNF-α-induced inflammation and apoptosis. SNCA gene transcription and α-syn protein expression were validated by q-PCR and Western blot (WB), respectively. Cell viability was measured, and apoptosis was evaluated by WB and terminal deoxynucleotidyl transferase nick end labeling methods. Alterations in LAG3 and TLR2 receptor levels were evaluated by immunofluorescent labeling, WB, and q-PCR. TNF-α not only increased inflammation but also increased endogenous and overexpressed α-syn levels. NAC treatment decreased expression of TLR2 and increased transcription of LAG3 receptor and diminished inflammation-mediated toxicity and cell death. Here, we demonstrate that NAC can reduce neuroinflammation that occurs as a result of alpha-synuclein overexpression, via a TLR2-associated pathway, making it a promising candidate for therapeutic intervention. Further studies are needed to elucidate molecular mechanisms and pathways related to neuroinflammation in PD and to develop possible new therapeutic approaches to slow the clinical progression of PD.

N-acetylcysteine does not alter neurometabolite levels in non-treatment seeking adolescents who use alcohol heavily: A preliminary randomized clinical trial

Current treatments for adolescent alcohol use disorder (AUD) are mainly psychosocial and limited in their efficacy. As such, pharmacotherapies are being investigated as potential adjunctive treatments to bolster treatment outcomes. N-acetylcysteine is a promising candidate pharmacotherapy for adolescent AUD because of its tolerability and demonstrated ability to modulate glutamatergic, GABAergic, and glutathione systems. The primary objective of this double-blind, placebo-controlled, within-subjects crossover preliminary investigation was to measure potential changes within glutamate + glutamine (Glx), GABA, and glutathione levels in the dorsal anterior cingulate cortex (dACC) using proton magnetic resonance spectroscopy during 10-days of N-acetylcysteine (1200 mg twice daily) compared to 10-days of placebo in non-treatment seeking adolescents who use alcohol heavily (N = 31; 55% female). Medication adherence was confirmed via video. Effects on alcohol use were measured using Timeline Follow-Back as an exploratory aim. Linear mixed effects models controlling for baseline metabolite levels, brain tissue composition, alcohol use, cannabis use, and medication adherence found no significant differences in Glx, GABA, or glutathione levels in the dACC after N-acetylcysteine compared to placebo. There were also no measurable effects on alcohol use; however, this finding was underpowered. Findings were consistent in the subsample of participants who met criteria for AUD (n = 19). The preliminary null findings in brain metabolite levels may be due to the young age of participants, relatively low severity of alcohol use, and non-treatment seeking status of the population investigated. Future studies can use these findings to conduct larger, well-powered studies within adolescents with AUD.

N-acetylcysteine Pharmacology and Applications in Rare Diseases-Repurposing an Old Antioxidant

N-acetylcysteine (NAC), a precursor of cysteine and, thereby, glutathione (GSH), acts as an antioxidant through a variety of mechanisms, including oxidant scavenging, GSH replenishment, antioxidant signaling, etc. Owing to the variety of proposed targets, NAC has a long history of use as a prescription product and in wide-ranging applications that are off-label as an over-the-counter (OTC) product. Despite its discovery in the early 1960s and its development for various indications, systematic clinical pharmacology explorations of NAC pharmacokinetics (PK), pharmacodynamic targets, drug interactions, and dose-ranging are sorely limited. Although there are anecdotal instances of NAC benefits in a variety of diseases, a comprehensive review of the use of NAC in rare diseases does not exist. In this review, we attempt to summarize the existing literature focused on NAC explorations in rare diseases targeting mitochondrial dysfunction along with the history of NAC usage, approved indications, mechanisms of action, safety, and PK characterization. Further, we introduce the research currently underway on other structural derivatives of NAC and acknowledge the continuum of efforts through pre-clinical and clinical research to facilitate further therapeutic development of NAC or its derivatives for rare diseases.

Effect of N-Acetylcysteine on Sleep: Impacts of Sex and Time of Day

Non-rapid eye movement sleep (NREMS) is accompanied by a decrease in cerebral metabolism, which reduces the consumption of glucose as a fuel source and decreases the overall accumulation of oxidative stress in neural and peripheral tissues. Enabling this metabolic shift towards a reductive redox environment may be a central function of sleep. Therefore, biochemical manipulations that potentiate cellular antioxidant pathways may facilitate this function of sleep. N-acetylcysteine increases cellular antioxidant capacity by serving as a precursor to glutathione. In mice, we observed that intraperitoneal administration of N-acetylcysteine at a time of day when sleep drive is naturally high accelerated the onset of sleep and reduced NREMS delta power. Additionally, N-acetylcysteine administration suppressed slow and beta electroencephalographic (EEG) activities during quiet wake, further demonstrating the fatigue-inducing properties of antioxidants and the impact of redox balance on cortical circuit properties related to sleep drive. These results implicate redox reactions in the homeostatic dynamics of cortical network events across sleep/wake cycles, illustrating the value of timing antioxidant administration relative to sleep/wake cycles. A systematic review of the relevant literature, summarized herein, indicates that this "chronotherapeutic hypothesis" is unaddressed within the clinical literature on antioxidant therapy for brain disorders such as schizophrenia. We, therefore, advocate for studies that systematically address the relationship between the time of day at which an antioxidant therapy is administered relative to sleep/wake cycles and the therapeutic benefit of that antioxidant treatment in brain disorders.

Critical Roles of the Cysteine-Glutathione Axis in the Production of γ-Glutamyl Peptides in the Nervous System

γ-Glutamyl moiety that is attached to the cysteine (Cys) residue in glutathione (GSH) protects it from peptidase-mediated degradation. The sulfhydryl group of the Cys residue represents most of the functions of GSH, which include electron donation to peroxidases, protection of reactive sulfhydryl in proteins via glutaredoxin, and glutathione conjugation of xenobiotics, whereas Cys-derived sulfur is also a pivotal component of some redox-responsive molecules. The amount of Cys that is available tends to restrict the capacity of GSH synthesis. In in vitro systems, cystine is the major form in the extracellular milieu, and a specific cystine transporter, xCT, is essential for survival in most lines of cells and in many primary cultivated cells as well. A reduction in the supply of Cys causes GPX4 to be inhibited due to insufficient GSH synthesis, which leads to iron-dependent necrotic cell death, ferroptosis. Cells generally cannot take up GSH without the removal of γ-glutamyl moiety by γ-glutamyl transferase (GGT) on the cell surface. Meanwhile, the Cys-GSH axis is essentially common to certain types of cells; primarily, neuronal cells that contain a unique metabolic system for intercellular communication concerning γ-glutamyl peptides. After a general description of metabolic processes concerning the Cys-GSH axis, we provide an overview and discuss the significance of GSH-related compounds in the nervous system.

Thiol disulfide homeostasis in psychiatric disorders: A comprehensive review

Thiol-disulfide couple maintains an intracellular redox status. Dynamic thiol-disulfide homeostasis acts crucial parts in metabolic processes involving signal mechanisms, inflammation, antioxidant defense. Thiol-disulfide homeostasis have been implicated in numerous diseases. In this comprehensive review we identified the studies that examined the thiol-disulfide homeostasis in psychiatric disorders. Most cases demonstrated alterations in thiol-disulfide homeostasis and in most of them the thiol-disulfide balance tended to change direction to the disulfide side, that is, to the oxidative side. Currently, the fact that N-acetylcysteine, a thiol-containing compound, is of great interest as a new treatment approach in psychiatric disorders and the role of glutathione, the most abundant thiol, in the brain highlights the importance of evaluating the thiol-disulfide balance in psychiatric disorders.

Neuroinflammation and Oxidative Stress in the Pathogenesis of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder (NDD) characterized by impairments in social communication, repetitive behaviors, restricted interests, and hyperesthesia/hypesthesia caused by genetic and/or environmental factors. In recent years, inflammation and oxidative stress have been implicated in the pathogenesis of ASD. In this review, we discuss the inflammation and oxidative stress in the pathophysiology of ASD, particularly focusing on maternal immune activation (MIA). MIA is a one of the common environmental risk factors for the onset of ASD during pregnancy. It induces an immune reaction in the pregnant mother’s body, resulting in further inflammation and oxidative stress in the placenta and fetal brain. These negative factors cause neurodevelopmental impairments in the developing fetal brain and subsequently cause behavioral symptoms in the offspring. In addition, we also discuss the effects of anti-inflammatory drugs and antioxidants in basic studies on animals and clinical studies of ASD. Our review provides the latest findings and new insights into the involvements of inflammation and oxidative stress in the pathogenesis of ASD.

Six weeks of N-acetylcysteine antioxidant in drinking water decreases pathological fiber branching in MDX mouse dystrophic fast-twitch skeletal muscle

Introduction: It has been proposed that an increased susceptivity to oxidative stress caused by the absence of the protein dystrophin from the inner surface of the sarcolemma is a trigger of skeletal muscle necrosis in the destructive dystrophin deficient muscular dystrophies. Here we use the mdx mouse model of human Duchenne Muscular Dystrophy to test the hypothesis that adding the antioxidant NAC at 2% to drinking water for six weeks will treat the inflammatory phase of the dystrophic process and reduce pathological muscle fiber branching and splitting resulting in a reduction of mass in mdx fast-twitch EDL muscles. Methods: Animal weight and water intake was recorded during the six weeks when 2% NAC was added to the drinking water. Post NAC treatment animals were euthanised and the EDL muscles dissected out and placed in an organ bath where the muscle was attached to a force transducer to measure contractile properties and susceptibility to force loss from eccentric contractions. After the contractile measurements had been made the EDL muscle was blotted and weighed. In order to assess the degree of pathological fiber branching mdx EDL muscles were treated with collagenase to release single fibers. For counting and morphological analysis single EDL mdx skeletal muscle fibers were viewed under high magnification on an inverted microscope. Results: During the six-week treatment phase NAC reduced body weight gain in three- to nine-week-old mdx and littermate control mice without effecting fluid intake. NAC treatment also significantly reduced the mdx EDL muscle mass and abnormal fiber branching and splitting. Discussion: We propose chronic NAC treatment reduces the inflammatory response and degenerative cycles in the mdx dystrophic EDL muscles resulting in a reduction in the number of complexed branched fibers reported to be responsible for the dystrophic EDL muscle hypertrophy.

Anti-Inflammatory Therapy as a Promising Target in Neuropsychiatric Disorders

This chapter analyzes the therapeutic potential of current anti-inflammatory drugs in treating psychiatric diseases from a neuro-immunological perspective. Based on the bidirectional brain-immune system relationship, the rationale is that a dysregulated inflammation contributes to the pathogenesis of psychiatric and neurological disorders, while the immunology function is associated with psychological variables like stress, affective disorders, and psychosis. Under certain social, psychological, and environmental conditions and biological factors, a healthy inflammatory response and the associated "sickness behavior," which are aimed to resolve a physical injury and microbial threat, become harmful to the central nervous system. The features and mechanisms of the inflammatory response are described across the main mental illnesses with a special emphasis on the profile of cytokines and the function of the HPA axis. Next, it is reviewed the potential clinical utility of immunotherapy (cytokine agonists and antagonists), glucocorticoids, unconventional anti-inflammatory agents (statins, minocycline, statins, and polyunsaturated fatty acids (PUFAs)), the nonsteroidal anti-inflammatory drugs (NSAIDs), and particularly celecoxib, a selective cyclooxygenase-2 (Cox-2) inhibitor, as adjuvants of conventional psychiatric medications. The implementation of anti-inflammatory therapies holds great promise in psychiatry. Because the inflammatory background may account for the etiology and/or progression of psychiatric disorders only in a subset of patients, there is a need to elucidate the immune underpinnings of the mental illness progression, relapse, and remission. The identification of immune-related bio-signatures will ideally assist in the stratification of the psychiatric patient to predict the risk of mental disease, the prognosis, and the response to anti-inflammatory therapy.

Can glutathione be a biomarker for suicide risk in women 18 months postpartum?

BACKGROUND

Suicide risk is prominent among the problems affecting populations, mainly due to the broad family, psychosocial and economic impact. Most individuals at suicidal risk have some mental disorder. There is considerable evidence that psychiatric disorders are accompanied by the activation of neuro-immune and neuro-oxidative pathways. The aim of the study is to evaluate the serum levels of oxidative stress biomarkers in women at risk of suicide after 18 months of postpartum.

METHODS

This is a case-control study, nested within a cohort study. From this cohort, 45 women [15 without mood disorders and 30 with mood disorders (Major depression and Bipolar disorder)] were selected at 18 months postpartum, the depression and suicide risk were assessed using the Mini-International Neuropsychiatric Interview Plus (MINI-Plus) instrument, module A and C, respectively. Blood was collected and stored for later analysis of the reactive species (DCFH), superoxide dismutase (SOD), and glutathione reduced (GSH). For data analysis, the SPSS program was used. To compare the nominal covariates with the outcome GSH levels, the Student's t-test or analysis of variance (ANOVA) was used. Spearman's correlation was performed for analysis between the quantitative covariates and the outcome. To analyze the interaction between the factors, multiple linear regression was performed. Bonferroni analysis was used as an additional/secondary result to visualize differences in glutathione levels according to risk severity. After the adjusted analysis, p-values < 0.05 were considered statistically significant.

RESULTS

The percentage of suicide risk observed in our sample of women at 18 months postpartum was 24.4% (n = 11). After adjusting for the independent variables, only the presence of suicide risk remained associated with the outcome (β = 0.173; p = 0.007), low levels of GSH at 18 months after postpartum. Likewise, we verified the difference in GSH levels according to the degree of suicide risk, observing a significant association between the differences in glutathione means in the group of women with moderate to high risk compared to the reference group (no suicide risk) (p = 0.009).

CONCLUSION

Our findings suggest that GSH may be a potential biomarker or etiologic factor in women at moderate to high risk of suicide.

The therapeutic effect of N-acetylcysteine as an add-on to methadone maintenance therapy medication in outpatients with substance use disorders: A randomized, double-blind, placebo-controlled clinical trial

OBJECTIVE

Patients with substance use disorders (SUD) under methadone maintenance therapy (MMT) are susceptible to a number of complications (psychological and metabolic disorders). Evidence studies have shown the roles of the glutamatergic system in addiction. N-Acetylcysteine (NAC) enhances extracellular glutamate, and is effective in the treatment of neuropsychiatric disorders. We assessed oral NAC as an add-on to MMT medication for the treatment of SUD.

METHODS

In the current randomized, double-blind, placebo-controlled clinical trial, outpatients with SUD under MMT who were 18-60 years old received 2400 mg/day NAC (n = 30) or placebo (n = 30) for 12 weeks. Psychological status and metabolic biomarkers were assessed at baseline and the end of the trial.

RESULTS

Compared with the placebo group, NAC treatment resulted in a significant improvement in depression score (β -2.36; 95% CI, -3.97, -0.76; p = .005), and anxiety score (β -1.82; 95% CI, -3.19, -0.44; p = .01). Furthermore, NAC treatment resulted in a significant elevation in total antioxidant capacity levels (β 72.28 mmol/L; 95% CI, 11.36, 133.19; p = .02), total glutathione (GSH) levels (β 81.84 μmol/L; 95% CI, 15.40, 148.28; p = .01), and a significant reduction in high-sensitivity C-reactive protein levels (β -0.89 mg/L; 95% CI, -1.50, -0.28; p = .005), and homeostasis model of assessment-insulin resistance (β -0.33; 95% CI, -0.65, -0.009; p = .04), compared with the placebo group.

CONCLUSION

In the current study, improvement in depression and anxiety symptoms as well as some metabolic profiles with NAC treatment for 12 weeks in outpatients with SUD under MMT was detected.

Effects of N-Acetylcysteine on the Proliferation, Hormone Secretion Level, and Gene Expression Profiles of Goat Ovarian Granulosa Cells

The purpose of this paper was to investigate the effects of N-acetylcysteine (NAC) on the proliferation, hormone secretion, and mRNA expression profiles of ovarian granulosa cells (GCs) in vitro. A total of 12 ovaries from 6 follicular-stage goats were collected for granulosa cell extraction. The optimum concentration of NAC addition was determined to be 200 μM via the Cell Counting Kit 8 (CCK-8) method. Next, GCs were cultured in a medium supplemented with 200 μM NAC (200 μM NAC group) and 0 μ M NAC (control group) for 48 h. The effects of 200 μM NAC on the proliferation of granulosa cells and hormones were studied by 5-ethynyl-2'-deoxyuridine (EdU) assay and enzyme-linked immunosorbent assay (ELISA). mRNA expression was analyzed by transcriptome sequencing. The results indicate that 200 μM NAC significantly increased cell viability and the proportion of cells in the S phase but promoted hormone secretion to a lesser degree. Overall, 122 differentially expressed genes (DEGs) were identified. A total of 51 upregulated and 71 downregulated genes were included. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that the most DEGs were enriched in terms of cell growth regulation, cell growth, neuroactive ligand-receptor interaction, cytokine-cytokine receptor interaction, the cAMP-signaling pathway, and the Wnt-signaling pathway. Seven genes related to granulosa cell proliferation were screened, IGFBP4, HTRA4, SST, SSTR1, WISP1, DAAM2, and RSPO2. The above results provide molecular theoretical support for NAC as a feed additive to improve follicle development and improve reproductive performance in ewes.

The Potential of N-acetyl Cysteine in Behavioral Addictions and Related Compulsive and Impulsive Behaviors and Disorders: a Scoping Review

Purpose of Review

Behavioral addictions (also termed disorders due to addictive behaviors) contain impulsive and compulsive features and have been shown to involve glutamate dysregulation. N-acetylcysteine (NAC), a well-tolerated cysteine pro-drug and antioxidant, may reduce addictive behaviors by restoring glutamate homeostasis. The current review details and discusses the use of NAC in behavioral addictions and related impulsive and compulsive behaviors, including gambling disorder, problematic use of the internet, problematic video gaming, compulsive sexual behavior, problematic shopping/buying, problematic stealing, repetitive self-injurious behavior, and binge eating disorder.

Recent Findings

Preliminary results have indicated the usefulness of NAC in gambling disorder, self-injurious behaviors, and compulsive sexual behaviors. Preclinical studies indicate that NAC is effective in improving binge eating behavior, but clinical trials are limited to a small open-label trial and case report. Studies are lacking on the efficacy of NAC in problematic use of the internet, problematic video gaming, problematic stealing, and problematic shopping/buying.

Summary

NAC demonstrates potential for use in behavioral addictions and compulsive behaviors, particularly in gambling disorder and self-injury. However, more studies are needed to assess the effectiveness of NAC in other behavioral addictions and the mechanisms by which NAC improves these conditions.

Global trends in research of glutamate in epilepsy during past two decades: A bibliometric analysis

Epilepsy affects more than 70 million people in the world. It is characterized by recurrent spontaneous seizures, and it is related to many neurological, cognitive, and psychosocial consequences. Glutamate neurotransmitter dysfunction has essential functions in the pathophysiology of epilepsy. In this work, bibliometric analysis was conducted to explore the trends, frontiers, and hotspots of the global scientific output of glutamate in epilepsy research in the past 20 years. The Science Citation Index Expanded of the Web of Science Core Collection (WoSCC) was searched to obtain information on publications and records published between 2002 and 2021. VOSviewer and CiteSpace were used to conduct bibliometric and visual analyses on the overall distribution of annual output, major countries, active institutions, journals, authors, commonly cited literature, and keywords. The impact and quality of the papers were assessed using the global citation score (GCS). Four thousand eight hundred ninety-one publications were retrieved in total. During the past two decades, the number of publications (Np) associated with glutamate in epilepsy has risen yearly. The United States has published the most papers; its H-index and number of citations are also the highest. The League of European Research Universities (LERU) was the most productive institution. In 2016, the total score of the paper written by Zhang Y was 854, ranking first. The keywords that appear most frequently are “epilepsy,” “glutamate,” “temporal lobe epilepsy (TLE),” “hippocampus,” and “seizures.” This study showed that although the publications related to epileptic glutamate fluctuated slightly, the Np increased overall. The United States is a great creator and influential country in this field. The first three authors are Eid, T., Aronica, E., and Smolders, I. “spectrum,” “animal model,” “inflammation,” “mutation,” “dysfunction,” and “prefrontal cortex” are increasing research hotspots. By recognizing the most critical indicators (researchers, countries, research institutes, and journals of glutamate release in epilepsy research), the research hotspot of glutamate in epilepsy could help countries, scholars, and policymakers in this field enhance their understanding of the role of glutamate in epilepsy and make decisions.

Gastrointestinal and liver disease in patients with schizophrenia: A narrative review

Schizophrenia is a severe mental illness which can have a devastating impact on an individual's quality of life. Comorbidities are high amongst patients and life expectancy is approximately 15 years less than the general population. Despite the well-known increased mortality, little is known about the impact of gastrointestinal and liver disease on patients with schizophrenia. We aimed to review the literature and to make recommendations regarding future care. Literature searches were performed on PubMed to identify studies related to gastrointestinal and liver disease in patients with schizophrenia. High rates of chronic liver disease were reported, with Non-Alcoholic Fatty Liver Disease being of particular concern; antipsychotics and metabolic syndrome were contributing factors. Rates of acute liver failure were low but have been associated with antipsychotic use and paracetamol overdose. Coeliac disease has historically been linked to schizophrenia; however, recent research suggests that a causal link is yet to be proven. Evidence is emerging regarding the relationships between schizophrenia and peptic ulcer disease, inflammatory bowel disease and irritable bowel syndrome; clinical vigilance regarding these conditions should be high. Patients with schizophrenia poorly engage with bowel cancer screening programmes, leading to late diagnosis and increased mortality. Clozapine induced constipation is a significant issue for many patients and requires close monitoring. There is a significant burden of gastrointestinal and liver disease amongst patients with schizophrenia. Better levels of support from all members of the medical team are essential to ensure that appropriate, timely care is provided.

Pharmacological interventions for the treatment of disordered and problem gambling

BACKGROUND

Pharmacological interventions for disordered and problem gambling have been employed in clinical practice. Despite the availability of several reviews of the efficacy of pharmacological interventions for disordered or problem gambling, few have employed systematic search strategies or compared different categories of pharmacological interventions. Systematic reviews of high-quality evidence are therefore essential to provide guidance regarding the efficacy of different pharmacological interventions for disordered or problem gambling.

OBJECTIVES

The primary aims of the review were to: (1) examine the efficacy of major categories of pharmacological-only interventions (antidepressants, opioid antagonists, mood stabilisers, atypical antipsychotics) for disordered or problem gambling, relative to placebo control conditions; and (2) examine the efficacy of these major categories relative to each other.  SEARCH METHODS: We searched the Cochrane Common Mental Disorders Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Embase, and PsycINFO (all years to 11 January 2022).

SELECTION CRITERIA

We included randomised trials evaluating a pharmacological intervention for the treatment of disordered or problem gambling. Eligible control conditions included placebo control groups or comparisons with another category of pharmacological intervention.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures, including systematic extraction of included study characteristics and results and risk of bias assessment. Our primary outcome was reduction in gambling symptom severity. Our secondary outcomes were reduction in gambling expenditure, gambling frequency, time spent gambling, depressive symptoms, anxiety symptoms, and functional impairment; and responder status. We evaluated treatment effects for continuous and dichotomous outcomes using standardised mean difference (SMD) and risk ratios (RR), respectively, employing random-effects meta-analyses. A minimum of two independent treatment effects were required for a meta-analysis to be conducted (with only meta-analytic findings reported in this abstract).

MAIN RESULTS

We included 17 studies in the review (n = 1193 randomised) that reported outcome data scheduled for end of treatment. Length of treatment ranged from 7 to 96 weeks.  Antidepressants: Six studies (n = 268) evaluated antidepressants, with very low to low certainty evidence suggesting that antidepressants were no more effective than placebo at post-treatment: gambling symptom severity (SMD -0.32, 95% CI -0.74 to 0.09, n = 225), gambling expenditure (SMD -0.27, 95% CI -0.60 to 0.06, n = 144), depressive symptoms (SMD -0.19, 95% CI -0.60 to 0.23, n = 90), functional impairment (SMD -0.15, 95% CI -0.53 to 0.22, n = 110), and responder status (RR 1.24, 95% CI 0.93 to 1.66, n = 268). Opioid antagonists: Four studies (n = 562) evaluated opioid antagonists, with very low to low certainty evidence showing a medium beneficial effect of treatment on gambling symptom severity relative to placebo at post-treatment (SMD -0.46, 95% CI -0.74 to -0.19, n = 259), but no difference between groups in responder status (RR 1.65, 95% CI 0.86 to 3.14, n = 562). Mood stabilisers: Two studies (n = 71) evaluated mood stabilisers (including anticonvulsants), with very low certainty evidence suggesting that mood stabilisers were no more effective than placebo at post-treatment: gambling symptom severity (SMD -0.92, 95% CI -2.24 to 0.39, n = 71), depressive symptoms (SMD -0.15, 95% CI -1.14 to 0.83, n = 71), and anxiety symptoms (SMD -0.17, 95% CI -0.64 to 0.30, n = 71). Atypical antipsychotics:Two studies (n = 63) evaluated the atypical antipsychotic olanzapine, with very low certainty evidence showing a medium beneficial effect of treatment on gambling symptom severity relative to placebo at post-treatment (SMD -0.59, 95% CI -1.10 to -0.08, n = 63). Comparative effectiveness: Two studies (n = 62) compared antidepressants with opioid antagonists, with very low certainty evidence indicating that antidepressants were no more effective than opioid antagonists on depressive symptoms (SMD 0.22, 95% CI -0.29 to 0.72, n = 62) or anxiety symptoms (SMD 0.21, 95% CI -0.29 to 0.72, n = 62) at post-treatment. Two studies (n = 58) compared antidepressants with mood stabilisers (including anticonvulsants), with very low certainty evidence indicating that antidepressants were no more effective than mood stabilisers on depressive symptoms (SMD 0.02, 95% CI -0.53 to 0.56, n = 58) or anxiety symptoms (SMD 0.16, 95% CI -0.39 to 0.70, n = 58) at post-treatment. Tolerability and adverse events: Several common adverse effects were reported by participants receiving antidepressants (e.g. headaches, nausea, diarrhoea/gastrointestinal issues) and opioid antagonists (e.g. nausea, dry mouth, constipation). There was little consistency in the types of adverse effects experienced by participants receiving mood stabilisers (e.g. tiredness, headaches, concentration difficulties) or atypical antipsychotics (e.g. pneumonia, sedation, increased hypomania). Discontinuation of treatment due to these adverse events was highest for opioid antagonists (10% to 32%), followed by antidepressants (4% to 31%), atypical antipsychotics (14%), and mood stabilisers (13%).

AUTHORS' CONCLUSIONS

This review provides preliminary support for the use of opioid antagonists (naltrexone, nalmefene) and atypical antipsychotics (olanzapine) to produce short-term improvements in gambling symptom severity, although a lack of available evidence precludes a conclusion regarding the degree to which these pharmacological agents can improve other gambling or psychological functioning indices. In contrast, the findings are inconclusive with regard to the effects of mood stabilisers (including anticonvulsants) in the treatment of disordered or problem gambling, and there is limited evidence to support the efficacy of antidepressants. However, these conclusions are based on very low to low certainty evidence characterised by a small number of included studies, high risk of bias, modest pooled sample sizes, imprecise estimates, moderate between-study heterogeneity, and exclusion of participants with psychiatric comorbidities. Moreover, there were insufficient studies to conduct meta-analyses on many outcome measures; to compare efficacy across and within major categories of interventions; to explore dosage effects; or to examine effects beyond post-treatment. These limitations suggest that, despite recommendations related to the administration of opioid antagonists in the treatment of disordered or problem gambling, pharmacological interventions should be administered with caution and with careful consideration of patient needs. A larger and more methodologically rigorous evidence base with longer-term evaluation periods is required before definitive conclusions can be drawn about the effectiveness and durability of pharmacological treatments for disordered or problem gambling.

N-acetylcysteine combined with insulin alleviates the oxidative damage of cerebrum via regulating redox homeostasis in type 1 diabetic mellitus canine

Neurodegenerative diseases are one of the major complications of type 1 diabetes mellitus (T1DM). The effect of insulin monotherapy on controlling blood glucose and neurodegeneration associated with diabetes is unsatisfactory. It is revealed that oxidative stress is a key element in T1DM. Therefore, N-acetylcysteine (NAC) was used together with insulin to investigate the therapeutic effect on neuronal damage in T1DM in this study. A total of 40 beagles were randomly divided into 5 groups (control group, DM group, insulin monotherapy group, NAC combined with insulin group, and NAC monotherapy group) to explore the effects of NAC on alleviating the oxidative damage in cerebrum. Our results showed that the contents of H₂O₂, 8-OHdg and MDA were apparently increased in DM group, while DNA and lipid oxidative damage was alleviated by the treatment of NAC and insulin. Histopathology revealed the sparse of neurofibrils and vacuolar degeneration in DM group. Additionally, compared with the control group, the mRNA expression levels of HO-1, nqo1, GCLC and GSTM1 were significantly decreased in DM group, while the opposite trend could be shown under NAC combined with insulin treatment. Meanwhile, the tight junction proteins of ZO-1, occludin and Claudin-1 were up-regulated with the treatment of NAC combined with insulin. Additionally, NAC further alleviated oxidative damage by enhancing the activity of GSH, Trx and TrxR and reducing the activity of catalase, GSSG and Grx to maintain redox homeostasis. These results demonstrated that NAC combined with insulin exerted protective effects against T1DM-induced cerebral injury via maintaining cerebral redox homeostasis.

N-Acetylcysteine Regenerates In Vivo Mercaptoalbumin

Human serum albumin (HSA) represents the most abundant plasma protein, with relevant antioxidant activity due to the presence of the sulfhydryl group on cysteine at position 34 (Cys34), the latter being one of the major target sites for redox-dependent modifications leading to the formation of mixed disulfide linkages with low molecular weight thiols. Thiolated forms of HSA (Thio-HSA) may be useful as markers of an unbalanced redox state and as a potential therapeutic target. Indeed, we have previously reported that albumin Cys34 can be regenerated in vitro by N-Acetylcysteine (NAC) through a thiol-disulfide breaking mechanism, with a full recovery of the HSA antioxidant and antiplatelet activities. With this case study, we aimed to assess the ability of NAC to regenerate native mercaptoalbumin (HSA-SH) and the plasma antioxidant capacity in subjects with redox unbalance, after oral and intravenous administration. A placebo-controlled crossover study, single-blinded, was performed on six hypertensive subjects, randomized into two groups, on a one-to-one basis with NAC (600 mg/die) or a placebo, orally and intravenously administered. Albumin isoforms, HSA-SH, Thio-HSA, and glutathione levels were evaluated by means of mass spectrometry. The plasma antioxidant activity was assessed by a fluorimetric assay. NAC, orally administered, significantly decreased the Thio-HSA levels in comparison with the pre-treatment conditions (T0), reaching the maximal effect after 60 min (−24.7 ± 8%). The Thio-HSA reduction was accompanied by a concomitant increase in the native HSA-SH levels (+6.4 ± 2%). After intravenous administration of NAC, a significant decrease of the Thio-HSA with respect to the pre-treatment conditions (T0) was observed, with a maximal effect after 30 min (−68.9 ± 10.6%) and remaining significant even after 6 h. Conversely, no effect on the albumin isoforms was detected with either the orally or the intravenously administered placebo treatments. Furthermore, the total antioxidant activity of the plasma significantly increased after NAC infusion with respect to the placebo (p = 0.0089). Interestingly, we did not observe any difference in terms of total glutathione corrected for hemoglobin, ruling out any effect of NAC on the intracellular glutathione and supporting its role as a disulfide-breaking agent. This case study confirms the in vitro experiments and demonstrates for the first time that NAC is able to regenerate mercaptoalbumin in vivo, allowing us to hypothesize that the recovery of Cys34 content can modulate in vivo oxidative stress and, hopefully, have an effect in oxidative-based diseases.