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CNS Drugs Nov 2022For decades, treatment of mood disorders, psychoses, anxiety and dementia have been confounded by limited efficacy and high rates of treatment resistance. Preclinical... (Meta-Analysis)
Meta-Analysis
BACKGROUND
For decades, treatment of mood disorders, psychoses, anxiety and dementia have been confounded by limited efficacy and high rates of treatment resistance. Preclinical and clinical evidence have highlighted disruption of cholinergic signalling in several neuropsychiatric conditions and examined intervention strategies including acetylcholinesterase inhibitors and nicotinic receptor-targeted intervention. However, the effectiveness of these approaches is often curtailed by on-target side effects. Post mortem studies implicate muscarinic receptor dysregulation in neuropsychiatric pathophysiology; therefore, we conducted a systematic review and meta-analysis to investigate the therapeutic efficacy and safety of muscarinic receptor-targeted interventions in adults with neuropsychiatric disorders.
METHODS
PubMed, EMBASE, PsycINFO, EBSCO and Web of Science were searched using relevant keywords from database inception to 7 August 2022. Randomised, double-blind, placebo-controlled studies were included if they investigated the effect of muscarinic receptor-targeted intervention in adults with a diagnosis of a neuropsychiatric disorder and were published in English. A narrative synthesis approach was adopted to describe the findings. Wherever three or more studies with a similar intervention were available, effect sizes were calculated, and a meta-analysis was performed. Cochrane risk-of-bias-2 tool was utilised to assess the risk of bias, and sensitivity analyses were performed to identify publication bias. Certainty analysis (high, moderate, low and/or very low) was conducted using GRADE criteria.
RESULTS
Overall, 33 studies met the inclusion criteria and 5 were included in the meta-analysis. Despite a limited pool with several different interventions, we found therapeutic efficacy of xanomeline (M/M agonist) in primary psychotic disorders plus behavioural and psychological symptoms of dementia. Scopolamine showed a significant antidepressant effect in a combined cohort of major depressive and bipolar disorders in the short-term outcome measure, but no effect following cessation of treatment. Results from bias assessments suggest "very low" certainty in the antidepressant effect of scopolamine. Critical limitations of the current literature included low power, high heterogeneity in the patient population and a lack of active comparators.
CONCLUSION
While the results are not definitive, findings on muscarinic receptor-targeted interventions in several mental disorders are promising in terms of efficacy and safety, specifically in treating schizophrenia, mood disorders, and behavioural and psychiatric symptoms of Alzheimer's disease. However, orthosteric muscarinic receptor-targeted interventions are associated with a range of peripheral adverse effects that are thought to be mediated via M/M receptors. The orthosteric binding site of muscarinic acetylcholine receptors is remarkably conserved, posing a challenge for subtype-selective interventions; nonetheless allosteric ligands with biased signalling pathways are now in development. We conclude that adequately powered prospective studies with subtype-selective interventions are required to determine the clinical effectiveness of muscarinic-receptor targeted interventions for the treatment of neuropsychiatric disorders.
Topics: Adult; Humans; Depressive Disorder, Major; Prospective Studies; Acetylcholinesterase; Treatment Outcome; Antidepressive Agents; Receptors, Muscarinic; Scopolamine Derivatives; Dementia; Randomized Controlled Trials as Topic
PubMed: 36269510
DOI: 10.1007/s40263-022-00964-8 -
ANZ Journal of Surgery Sep 2023Chronic intestinal pseudo-obstruction (CIPO) may be a primary or secondary phenomenon and is often multifactorial. Treatment is largely directed at improving colonic... (Review)
Review
BACKGROUND
Chronic intestinal pseudo-obstruction (CIPO) may be a primary or secondary phenomenon and is often multifactorial. Treatment is largely directed at improving colonic motility. The use of cholinesterase inhibitors such as pyridostigmine has been hypothesized to increase acetylcholine in the bowel, improving symptoms and transit times.
METHODS
A systematic review of the use of pyridostigmine in CIPO was conducted using scientific and commercial search engines identifying scientific studies enrolling adult human subjects, published from 2000 to 2022 in the English language.
RESULTS
Four studies were identified including two randomized controlled trials (RCT) and two observational studies. The studies had heterogenous inclusion criteria, dosing regimens and reported outcomes. Two studies were identified as being at high risk of bias. All studies reported improved patient outcomes with use of pyridostigmine, and low rates (4.3%) of mild cholinergic side effects. No major side effects were reported.
CONCLUSION
The use of pyridostigmine in management of CIPO is biologically plausible due to its ability to increase colonic motility, and early studies on its role are uniformly suggestive of benefit with low side-effect profile. Four clinical studies have been conducted to date, with small sample sizes, heterogeneity and high risk of bias. Further high-quality studies are required to enable assessment of pyridostigmine's utility as an effective management strategy in CIPO.
Topics: Adult; Humans; Pyridostigmine Bromide; Gastrointestinal Motility; Intestinal Pseudo-Obstruction; Cholinesterase Inhibitors; Chronic Disease
PubMed: 37132128
DOI: 10.1111/ans.18478 -
European Journal of Neurology Jan 2022Sialorrhea often happens in patients with neurologic disorders, and botulinum toxin (BoNT), which inhibits acetylcholine activation, may be an effective treatment for... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND PURPOSE
Sialorrhea often happens in patients with neurologic disorders, and botulinum toxin (BoNT), which inhibits acetylcholine activation, may be an effective treatment for drooling. This systematic review and meta-analysis of randomized control trials aims to evaluate the efficacy and safety of BoNT in adults and children with sialorrhea due to neurological disorders.
METHODS
The PubMed, Embase, and Cochrane databases were searched for relevant studies published before August 2021. The pooled estimate of outcomes was calculated using a random effect model.
RESULTS
The review included 17 studies involving 981 patients. Compared with placebo, both BoNT type A (BoNT-A) and BoNT type B (BoNT-B) alleviated drooling frequency and severity (mean difference, 95% CI; BoNT-A: -1.20, -1.89 to -0.51; BoNT-B: -1.62, -2.07 to -1.17), reduced saliva weight (BoNT-A: -1.70, -2.30 to -1.10; BoNT-B: -1.12, -1.97 to -0.27), and improved global impression of change (BoNT-A: -1.30, -1.73 to -0.86; BoNT-B: -1.58, -1.95 to -1.21) in adults 4 weeks postinjection. BoNT-B remained effective at 12 weeks. In children, BoNT-A and BoNT-B alleviated sialorrhea symptoms (BoNT-A: -1.63, -2.42 to -0.85; BoNT-B: -5.20, -6.03 to -4.37) and BoNT-A reduced saliva weight (-0.77, -1.54 to 0.00) at 4 weeks postinjection. After 12 weeks, BoNT-B remained efficacious. Most adverse effects (AEs) were mild to moderate and self-limited.
CONCLUSIONS
There is moderate certainty of evidence (COE) that either BoNT-A or BoNT-B could relieve sialorrhea after 4 and 12 weeks of follow-up without significantly more severe AEs in adults. However, the COE is very low to low in children.
Topics: Botulinum Toxins, Type A; Child; Humans; Neuromuscular Agents; Sialorrhea; Treatment Outcome
PubMed: 34449931
DOI: 10.1111/ene.15083 -
Age and Ageing Sep 2023Anticholinergic medications block the neurotransmitter acetylcholine in the brain and peripheral nervous system. Many medications have anticholinergic properties, and... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Anticholinergic medications block the neurotransmitter acetylcholine in the brain and peripheral nervous system. Many medications have anticholinergic properties, and the cumulative effect of these medications is termed anticholinergic burden. Increased anticholinergic burden can have short-term side effects such as dry mouth, blurred vision and urinary retention as well as long-term effects including dementia, worsening physical function and falls.
METHODS
We carried out a systematic review (SR) with meta-analysis (MA) looking at randomised controlled trials addressing interventions to reduce anticholinergic burden in older adults.
RESULTS
We identified seven papers suitable for inclusion in our SR and MA. Interventions included multi-disciplinary involvement in medication reviews and deprescribing of AC medications. Pooled data revealed no significant difference in outcomes between control and intervention group for falls (OR = 0.76, 95% CI: 0.52-1.11, n = 647), cognition (mean difference = 1.54, 95% CI: -0.04 to 3.13, n = 405), anticholinergic burden (mean difference = 0.04, 95% CI: -0.11 to 0.18, n = 710) or quality of life (mean difference = 0.04, 95% CI: -0.04 to 0.12, n = 461).
DISCUSSION
Overall, there was no significant difference with interventions to reduce anticholinergic burden. As we did not see a significant change in anticholinergic burden scores following interventions, it is likely other outcomes would not change. Short follow-up time and lack of training and support surrounding successful deprescribing may have contributed.
Topics: Humans; Aged; Quality of Life; Cholinergic Antagonists; Acetylcholine; Brain; Cognition
PubMed: 37740900
DOI: 10.1093/ageing/afad176 -
Neurology Oct 2023Ocular myasthenia gravis (OMG) is an autoimmune disorder resulting in ocular symptoms such as diplopia and ptosis. The proportion of patients who convert to secondary... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVES
Ocular myasthenia gravis (OMG) is an autoimmune disorder resulting in ocular symptoms such as diplopia and ptosis. The proportion of patients who convert to secondary generalized myasthenia gravis (SGMG) reported in the literature has been varied. The aim of this systematic review was to determine the clinical characteristics of patients with OMG and the proportion of SGMG conversion.
METHODS
We conducted an electronic database search for randomized controlled trials, prospective nonrandomized studies, observational studies, and retrospective studies in EMBASE, CENTRAL, MEDLINE, and Web of Science. We included studies with patients with OMG who initially presented with ocular symptoms and signs only and were seen in clinical practice, reporting on the characteristics and outcomes of SGMG. We excluded studies with pediatric and congenital myasthenia gravis populations. Eligible studies included articles written in any language and containing data on patients with OMG. The main outcome measured was the proportion of patients with OMG who converted to SGMG and risk factors associated with secondary generalization of OMG. Two independent reviewers screened titles and abstracts and extracted data from full texts, reporting findings according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The methodology was evaluated using the Joanna Briggs Institute critical appraisal forms. PROSPERO registration number: CRD2021285257.
RESULTS
Thirty-one studies were included in the quantitative and qualitative analysis. The proportion of generalization ranged from 11% to 84%. The pooled proportion was 39% (95% CI 32%-47%, = 95.86%, < 0.001 unweighted, low certainty). The pooled risk ratio of female sex for conversion to SGMG was 1.06 (95% CI 0.96-1.17, = 0% = 0.614, 21 studies included, very low certainty), and the pooled risk ratio of acetylcholine receptor (AChR) positivity was 1.30 (95% CI 1.05-1.56, = 0% = 0.455, 16 studies included, very low certainty).
DISCUSSION
Risk factors such as female sex and anti-AChR positivity have been identified to have possible associations with SGMG, but there are not enough quality observational studies. There is a need for a prospective global database of patients with OMG, including all countries with different populations.
Topics: Humans; Female; Child; Retrospective Studies; Myasthenia Gravis; Receptors, Cholinergic; Risk Factors; Blepharoptosis
PubMed: 37643888
DOI: 10.1212/WNL.0000000000207642 -
Journal of Neurophysiology Aug 2023Spinal motoneurons contain many ion channels and receptors upon which various cannabinoids are known to act. This scoping review involved the synthesis of evidence from... (Review)
Review
Spinal motoneurons contain many ion channels and receptors upon which various cannabinoids are known to act. This scoping review involved the synthesis of evidence from literature published before August 2022 about the effects of cannabinoids on quantifiable measures of motoneuron output. Four databases (MEDLINE, Embase, PsycINFO, and Web of Science CoreCollection) were queried and 4,237 unique articles were retrieved. Twenty-three studies met the inclusion criteria, and the findings from these studies were grouped according to four emergent themes: rhythmic motoneuron output, afferent feedback integration, membrane excitability, and neuromuscular junction transmission. This synthesis of evidence suggests that CB1 agonists can increase the frequency of cyclical patterns of motoneuron output (i.e., fictive locomotion). Furthermore, a majority of the evidence indicates that activating CB1 receptors at motoneuron synapses promotes excitation of motoneurons by enhancing excitatory synaptic transmission and depressing inhibitory synaptic transmission. The collated study results reveal variable effects of cannabinoids on acetylcholine release at the neuromuscular junction, and the influence of cannabinoids in this area requires more work to ensure precision of findings for CB1 agonist and antagonist impact. Altogether, these reports indicate that the endocannabinoid system is integral within the final common pathway and can impact motor output. This review contributes to understanding the effects of endocannabinoids on synaptic integration at the motoneuron and modulation of motor output.
Topics: Cannabinoids; Motor Neurons; Synapses; Synaptic Transmission; Neuromuscular Junction
PubMed: 37283484
DOI: 10.1152/jn.00460.2022 -
Frontiers in Immunology 2021Myasthenia gravis (MG) is an autoimmune disease primarily mediated by acetylcholine receptor antibodies (AChR-Ab), cellular immune dependence, and complement system... (Review)
Review
Myasthenia gravis (MG) is an autoimmune disease primarily mediated by acetylcholine receptor antibodies (AChR-Ab), cellular immune dependence, and complement system involvement. Since the AChR on the postsynaptic membrane is destroyed by an immune attack, sufficient endplate potential cannot be generated, resulting in the development of a synaptic transmission disorder at the neuromuscular junction and in muscle weakness. The role of the complement system in MG has been demonstrated in animal models and clinical tests, and it has been determined that complement inhibition in patients with MG can prevent disease induction and reverse its progression. Eculizumab is a humanized monoclonal antibody that inhibits the cleavage of complement protein C5 and prevents autoimmune damage; additionally, it has received subsequent approval by the Federal Drug Administration of the United States for MG treatment. However, various concerns regarding the use of eculizumab persist. In this review, we have discussed the treatment time, cost effectiveness, long-term efficacy, and tolerability of eculizumab for MG treatment. We have also summarized historical information and have presented perspectives on this new therapeutic modality.
Topics: Animals; Antibodies, Monoclonal, Humanized; Clinical Trials as Topic; Combined Modality Therapy; Complement Inactivating Agents; Complement System Proteins; Disease Management; Disease Susceptibility; Drug Development; Humans; Myasthenia Gravis; Treatment Outcome
PubMed: 34456922
DOI: 10.3389/fimmu.2021.715036 -
BMC Ophthalmology Jul 2023Dry eye disease (DED) is caused by a persistently unstable tear film leading to ocular discomfort and is treated mainly with tear supplementation. There is emerging... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Dry eye disease (DED) is caused by a persistently unstable tear film leading to ocular discomfort and is treated mainly with tear supplementation. There is emerging evidence that nicotinic acetylcholine receptor (nAChR) agonists (e.g., varenicline and simpinicline) nasal sprays are effective for DED. Our systematic review and meta-analysis assessed the efficacy and safety of varenicline nasal spray (VNS) for DED treatment.
METHODS
The Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched. Only randomized controlled trials (RCTs) that evaluated the efficacy of VNS versus placebo were included. The efficacy endpoint was the mean change in the anesthetized Schirmer test score (STS), a measure of basal tear production, from baseline. The safety endpoints were serious adverse events (SAEs) and adverse events (AEs). The standardized mean difference (SMD) was used for continuous outcomes, while the risk ratio (RR) was used to demonstrate dichotomous variables. The certainty of the evidence was rated utilizing the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. The risk of bias assessment was conducted using the Revised Cochrane risk of bias tool for randomized trials.
RESULTS
Three RCTs (n = 1063) met the eligibility criteria. All RCTs had a low risk of bias. The meta-analysis found a statistically significant increase in the mean STS change from baseline on day 28. The pooled analysis found no significant difference between VNS and placebo in the frequency of SAEs and ocular AEs. However, VNS had a significant effect on developing nasal cavity-related AEs.
CONCLUSION
VNS caused a highly significant improvement regarding the efficacy endpoint but caused an increased frequency of some nasal cavity-related AEs (i.e., cough and throat irritation). However, it caused neither SAEs nor ocular AEs. Included studies had a low risk of bias.
Topics: Humans; Nasal Sprays; Varenicline; Dry Eye Syndromes
PubMed: 37452334
DOI: 10.1186/s12886-023-03069-y -
Environmental Research Dec 2023Per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) are... (Meta-Analysis)
Meta-Analysis
Associations of per- and polyfluoroalkyl substances, polychlorinated biphenyls, organochlorine pesticides, and polybrominated diphenyl ethers with oxidative stress markers: A systematic review and meta-analysis.
BACKGROUND
Per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) are intentionally produced persistent organic pollutants (POPs) that are resistant to environmental degradation. Previous in-vitro and in-vivo studies have shown that POPs can induce oxidative stress, which is linked to neurodegenerative diseases, cardiovascular diseases, and cancer. However, findings in epidemiological studies are inconsistent and an evidence synthesis study is lacking to summarize the existing literature and explore research gaps.
OBJECTIVE
We evaluated the effects of PFAS, PCBs, OCPs, and PBDEs, on oxidative stress biomarkers in epidemiological studies.
METHODS
A literature search was conducted in PubMed, Embase, and Cochrane CENTRAL to identify all published studies related to POPs and oxidative stress up to December 7, 2022. We included human observational studies reporting at least one exposure to POPs and an oxidative stress biomarker of interest. Random-effects meta-analyses on standardized regression coefficients and effect direction plots with one-tailed sign tests were used for quantitative synthesis.
RESULTS
We identified 33 studies on OCPs, 35 on PCBs, 49 on PFAS, and 12 on PBDEs. Meta-analyses revealed significant positive associations of α-HCH with protein carbonyls (0.035 [0.017, 0.054]) and of 4'4-DDE with malondialdehyde (0.121 [0.056, 0.187]), as well as a significant negative association between 2'4-DDE and total antioxidant capacity (TAC) (-0.042 [-0.079, -0.004]), all β [95%CI]. Sign tests showed a significant positive association between PCBs and malondialdehyde (p = 0.03). Additionally, we found significant negative associations of OCPs with acetylcholine esterase (p = 0.02) and paraoxonase-1 (p = 0.03). However, there were inconsistent associations of OCPs with superoxide dismutase, glutathione peroxidase, and catalase.
CONCLUSIONS
Higher levels of OCPs were associated with increased levels of oxidative stress through increased pro-oxidant biomarkers involving protein oxidation, DNA damage, and lipid peroxidation, as well as decreased TAC. These findings have the potential to reveal the underlying mechanisms of POPs toxicity.
Topics: Humans; Antioxidants; Biomarkers; Environmental Pollutants; Fluorocarbons; Halogenated Diphenyl Ethers; Hydrocarbons, Chlorinated; Malondialdehyde; Oxidative Stress; Pesticides; Polychlorinated Biphenyls
PubMed: 37813138
DOI: 10.1016/j.envres.2023.117308 -
Frontiers in Pharmacology 2020Fatigue, as a complex, multidimensional symptom, is associated with many physical illnesses. C. A. Mey (PG) is an important herbal drug which has been used for...
BACKGROUND
Fatigue, as a complex, multidimensional symptom, is associated with many physical illnesses. C. A. Mey (PG) is an important herbal drug which has been used for benefiting Qi for thousand years. C. A. Mey and its compounds (PGC) possess various pharmacological activities, including anti-fatigue. Here, we conducted a systematic review of both randomized clinical trials (RCTs) and preclinical animal studies to investigate the efficacy and safety of PGC for fatigue.
METHODS
Electronic searches were performed in 7 databases from the time of each database's inception to August 2019. The methodological quality of RCTs was assessed using 7-item checklist recommended by Cochrane Collaboration or by the CAMARADES 10-item quality checklist. All the data were analyzed using Rev-Man 5.3 and Stata SE software.
RESULTS
Eight eligible RCTs and 30 animal studies were identified. The risk of bias scores in RCTs ranged from 4/7 to 7/7, and of animal studies varied from 4/10 to 7/10. Meta-analyses showed that PGC was superior to placebo according to their respective fatigue scales, heart rate recovery, and clinical effect (P < 0.05). There were a similar number of adverse effects between PGC and placebo group (P > 0.05). Meta-analyses showed that PGC can significantly decrease level of blood lactate, blood urea nitrogen, creatine kinase, malondialdehyde, and lactic dehydrogenase in serum, level of malondialdehyde in liver and level of gamma-aminobutyric acid, 5-hydroxytryptamine in brain tissue, and increase swimming time, level of glutathione peroxidase, glucose, superoxide dismutase in serum, level of glycogen and activity of superoxide dismutase, glutathione peroxidase, and catalase in skeletal muscle, level of hepatic glycogen in liver and level of dopamine, acetylcholine in brain tissue, compared with control (P < 0.05). Meta-analyses showed no significant difference in animal body weight between PGC and control (P > 0.05).
CONCLUSION
The present findings supported, to a certain degree, that PGC can be recommended for routine use in fatigue. The possible mechanism of PGC resists fatigue, mainly through antioxidant stress, regulating carbohydrate metabolism, delaying the accumulation of metabolites, promoting mitochondrial function, neuroprotection, antiapoptosis, and regulating neurotransmitter disorder in central nervous system.
PubMed: 32765262
DOI: 10.3389/fphar.2020.01031