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The Cochrane Database of Systematic... May 2017Molluscum contagiosum is a common skin infection that is caused by a pox virus and occurs mainly in children. The infection usually resolves within months in people... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Molluscum contagiosum is a common skin infection that is caused by a pox virus and occurs mainly in children. The infection usually resolves within months in people without immune deficiency, but treatment may be preferred for social and cosmetic reasons or to avoid spreading the infection. A clear evidence base supporting the various treatments is lacking.This is an update of a Cochrane Review first published in 2006, and updated previously in 2009.
OBJECTIVES
To assess the effects of specific treatments and management strategies, including waiting for natural resolution, for cutaneous, non-genital molluscum contagiosum in people without immune deficiency.
SEARCH METHODS
We updated our searches of the following databases to July 2016: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We searched six trial registers and checked the reference lists of included studies and review articles for further references to relevant randomised controlled trials. We contacted pharmaceutical companies and experts in the field to identify further relevant randomised controlled trials.
SELECTION CRITERIA
Randomised controlled trials of any treatment of molluscum contagiosum in people without immune deficiency. We excluded trials on sexually transmitted molluscum contagiosum and in people with immune deficiency (including those with HIV infection).
DATA COLLECTION AND ANALYSIS
Two review authors independently selected studies, assessed methodological quality, and extracted data from selected studies. We obtained missing data from study authors where possible.
MAIN RESULTS
We found 11 new studies for this update, resulting in 22 included studies with a total of 1650 participants. The studies examined the effects of topical (20 studies) and systemic interventions (2 studies).Among the new included studies were the full trial reports of three large unpublished studies, brought to our attention by an expert in the field. They all provided moderate-quality evidence for a lack of effect of 5% imiquimod compared to vehicle (placebo) on short-term clinical cure (4 studies, 850 participants, 12 weeks after start of treatment, risk ratio (RR) 1.33, 95% confidence interval (CI) 0.92 to 1.93), medium-term clinical cure (2 studies, 702 participants, 18 weeks after start of treatment, RR 0.88, 95% CI 0.67 to 1.14), and long-term clinical cure (2 studies, 702 participants, 28 weeks after start of treatment, RR 0.97, 95% CI 0.79 to 1.17). We found similar but more certain results for short-term improvement (4 studies, 850 participants, 12 weeks after start of treatment, RR 1.14, 95% CI 0.89 to 1.47; high-quality evidence). For the outcome 'any adverse effect', we found high-quality evidence for little or no difference between topical 5% imiquimod and vehicle (3 studies, 827 participants, RR 0.97, 95% CI 0.88 to 1.07), but application site reactions were more frequent in the groups treated with imiquimod (moderate-quality evidence): any application site reaction (3 studies, 827 participants, RR 1.41, 95% CI 1.13 to 1.77, the number needed to treat for an additional harmful outcome (NNTH) was 11); severe application site reaction (3 studies, 827 participants, RR 4.33, 95% CI 1.16 to 16.19, NNTH over 40).For the following 11 comparisons, there was limited evidence to show which treatment was superior in achieving short-term clinical cure (low-quality evidence): 5% imiquimod less effective than cryospray (1 study, 74 participants, RR 0.60, 95% CI 0.46 to 0.78) and 10% potassium hydroxide (2 studies, 67 participants, RR 0.65, 95% CI 0.46 to 0.93); 10% Australian lemon myrtle oil more effective than olive oil (1 study, 31 participants, RR 17.88, 95% CI 1.13 to 282.72); 10% benzoyl peroxide cream more effective than 0.05% tretinoin (1 study, 30 participants, RR 2.20, 95% CI 1.01 to 4.79); 5% sodium nitrite co-applied with 5% salicylic acid more effective than 5% salicylic acid alone (1 study, 30 participants, RR 3.50, 95% CI 1.23 to 9.92); and iodine plus tea tree oil more effective than tea tree oil (1 study, 37 participants, RR 0.20, 95% CI 0.07 to 0.57) or iodine alone (1 study, 37 participants, RR 0.07, 95% CI 0.01 to 0.50). Although there is some uncertainty, 10% potassium hydroxide appears to be more effective than saline (1 study, 20 participants, RR 3.50, 95% CI 0.95 to 12.90); homeopathic calcarea carbonica appears to be more effective than placebo (1 study, 20 participants, RR 5.57, 95% CI 0.93 to 33.54); 2.5% appears to be less effective than 5% solution of potassium hydroxide (1 study, 25 participants, RR 0.35, 95% CI 0.12 to 1.01); and 10% povidone iodine solution plus 50% salicylic acid plaster appears to be more effective than salicylic acid plaster alone (1 study, 30 participants, RR 1.43, 95% CI 0.95 to 2.16).We found no statistically significant differences for other comparisons (most of which addressed two different topical treatments). We found no randomised controlled trial evidence for expressing lesions or topical hydrogen peroxide.Study limitations included no blinding, many dropouts, and no intention-to-treat analysis. Except for the severe application site reactions of imiquimod, none of the evaluated treatments described above were associated with serious adverse effects (low-quality evidence). Among the most common adverse events were pain during application, erythema, and itching. Included studies of the following comparisons did not report adverse effects: calcarea carbonica versus placebo, 10% povidone iodine plus 50% salicylic acid plaster versus salicylic acid plaster, and 10% benzoyl peroxide versus 0.05% tretinoin.We were unable to judge the risk of bias in most studies due to insufficient information, especially regarding concealment of allocation and possible selective reporting. We considered five studies to be at low risk of bias.
AUTHORS' CONCLUSIONS
No single intervention has been shown to be convincingly effective in the treatment of molluscum contagiosum. We found moderate-quality evidence that topical 5% imiquimod was no more effective than vehicle in terms of clinical cure, but led to more application site reactions, and high-quality evidence that there was no difference between the treatments in terms of short-term improvement. However, high-quality evidence showed a similar number of general side effects in both groups. As the evidence found did not favour any one treatment, the natural resolution of molluscum contagiosum remains a strong method for dealing with the condition.
Topics: Adjuvants, Immunologic; Aminoquinolines; Anti-Infective Agents, Local; Benzoyl Peroxide; Cimetidine; Humans; Hydroxides; Imiquimod; Molluscum Contagiosum; Myrtus; Olive Oil; Phytotherapy; Plant Oils; Potassium Compounds; Povidone-Iodine; Randomized Controlled Trials as Topic; Remission, Spontaneous; Salicylic Acid; Sodium Nitrite
PubMed: 28513067
DOI: 10.1002/14651858.CD004767.pub4 -
Journal of Periodontal Research Jan 2022The present systematic review examined the available evidence on distinctive salivary ion profile in periodontitis compared to periodontal health and provided a... (Review)
Review
OBJECTIVES
The present systematic review examined the available evidence on distinctive salivary ion profile in periodontitis compared to periodontal health and provided a qualitative assessment of the literature.
BACKGROUND
Macro and trace elements are essential for cellular physiology, and their changes in biological fluids can be revelatory of an underlying pathological status.
METHODS
Data from relevant studies identified from PubMed, Embase, and Scopus databases were retrieved to answer the following PECO question: "In systemically healthy individuals, are there any differences in any salivary macro or trace element concentration between periodontally healthy subjects (H) and patients with periodontitis (P)?" Quality of included studies was rated using a modified version of the QUADOMICS tool. A consistency analysis was performed to identify significantly discriminant chemical elements.
RESULTS
After the screening of 873 titles, 13 studies were included reporting data on 22 different elements. Among them, levels of sodium and potassium were consistently and significantly higher in P compared to H. Conflicting results were found for all the other elements, despite concentration of calcium, copper, and manganese mostly increased in saliva of P. Levels of magnesium were found higher in P than in H in 2 studies but lower in 3. Zinc resulted significantly increased in saliva from H compared to P individuals in 2 studies, but one study reported opposite results. Four studies were considered as high quality, while reporting of operative protocols and statistical analysis was a major limitation for the others. Due to high methodologic heterogeneity, meta-analysis was not performed.
CONCLUSIONS
Levels of macro or trace elements were differentially identified in saliva across diverse periodontal conditions, having a major potential for investigation of oral homeostasis and for high-resolution periodontal diagnosis. Products of inflammatory physiologic cellular impairment, such as sodium and potassium, were the most consistently associated with periodontitis (PROSPERO CRD42021235744).
Topics: Biomarkers; Humans; Periodontal Diseases; Periodontitis; Saliva; Trace Elements
PubMed: 34837226
DOI: 10.1111/jre.12956 -
Journal of Dental Research May 2020The goal of this systematic review and network meta-analysis was to compare the relative effects of toothpaste formulations for dentin hypersensitivity (DH), tested in...
The goal of this systematic review and network meta-analysis was to compare the relative effects of toothpaste formulations for dentin hypersensitivity (DH), tested in randomized controlled trials (RCTs). We searched 7 databases to February 2019. Paired reviewers independently screened studies, extracted data, and performed risk of bias assessment. The outcome of interest was painful response measured through tactile, cold, and air stimuli. We conducted a random-effects Bayesian network meta-analysis using standardized mean difference (SMD) and their credible intervals (CIs) as the measure of effect for each pain stimuli. We assessed certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. We included 125 RCTs (12,541 patients). For tactile stimulus, the following active ingredients showed large beneficial effects compared to fluoride with moderate certainty of evidence (SMD; 95% CI): potassium + stannous fluoride (SnF) (3.05; 1.69-4.41), calcium sodium phosphosilicate (CSP) (2.14; 0.75-3.53), SnF (2.02; 1.06-2.99), potassium + hydroxyapatite (2.47; 0.3-4.64), strontium (1.43; 0.46-2.41), and potassium (1.23; 0.48-1.98). For cold stimulus, CSP showed large beneficial effects compared to fluoride (3.93; 0.34-7.53) with moderate certainty; for air stimulus, arginine (2.22; 1.45-2.99), potassium + hydroxyapatite (2.44; 0.33-4.55), potassium + SnF (2.28; 0.87-3.69), CSP (1.98; 0.99-2.98), and SnF (1.9; 1.03-2.77) showed large beneficial effects compared to fluoride with moderate to high certainty. Most toothpaste formulations showed evidence of superiority against placebo or fluorides (amine fluoride, sodium monofluorophosphate, or sodium fluoride). CSP was most beneficial for all 3 stimuli with high to moderate certainty. SnF alone and potassium combined with SnF or hydroxyapatite were beneficial for tactile and air stimulus with high to moderate certainty. Arginine was beneficial for air stimulus, and strontium and potassium were beneficial for tactile stimulus, with moderate certainty.
Topics: Bayes Theorem; Dentin Desensitizing Agents; Dentin Sensitivity; Double-Blind Method; Fluorides; Humans; Network Meta-Analysis; Phosphates; Sodium Fluoride; Toothpastes; Treatment Outcome
PubMed: 32037944
DOI: 10.1177/0022034520903036 -
Clinical Oral Investigations Jul 2021To conduct a systematic review and meta-analysis to evaluate the risk and intensity of tooth sensitivity (TS) after topical application of desensitizers containing... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To conduct a systematic review and meta-analysis to evaluate the risk and intensity of tooth sensitivity (TS) after topical application of desensitizers containing potassium nitrate before dental bleaching.
METHODS
We searched PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and SIGLE. We also surveyed gray literature without restrictions. We meta-analyzed the data using the random-effects model to compare potassium nitrate and placebo in terms of risk and intensity of TS and color change (∆SGU or ∆E). The quality of the evidence was rated using the GRADE approach. The risk of bias (RoB) of the included studies was analyzed using the Cochrane RoB tool.
RESULTS
After the database screening, 24 articles remained. A significant 12% lower risk for the groups where desensitizing agents were applied (p = 0.02), with a risk ratio of 0.88 (95% CI 0.78 to 0.98). About the intensity of TS, a significant average mean difference of - 0.77 units of VAS units (95%CI - 1.34 to - 0.19; p = 0.01) in favor of the desensitizer group. In the NRS scale, a significant average mean difference of - 0.36 (95% CI - 0.61 to - 0.12; p value = 0.004) in favor of the desensitizer group. No significant difference was observed in color change (p > 0.28) in ∆SGU and ∆E.
CONCLUSIONS
Although a significant reduction in the risk and intensity of TS was observed in groups treated with a potassium nitrate at some point during the bleaching, the clinical significance of this reduction is subtle and clinically questionable. Color change is not affected by the use of agents.
CLINICAL RELEVANCE
The reduction in the risk and intensity of TS with the topical application of potassium nitrate-based desensitizing agents in dental bleaching is subtle and maybe clinically questionable.
Topics: Dentin Sensitivity; Humans; Hydrogen Peroxide; Nitrates; Potassium Compounds; Tooth Bleaching; Tooth Bleaching Agents
PubMed: 34075489
DOI: 10.1007/s00784-021-03994-6 -
Archives of Biochemistry and Biophysics Oct 2021Mechanical environments were associated with alterations in bone metabolism. Ion channels present on bone cells are indispensable for bone metabolism and can be directly...
Mechanical environments were associated with alterations in bone metabolism. Ion channels present on bone cells are indispensable for bone metabolism and can be directly or indirectly activated by mechanical stimulation. This review aimed to discuss the literature reporting the mechanical regulatory effects of ion channels on bone cells and bone tissue. An electronic search was conducted in PubMed, Embase and Web of Science. Studies about mechanically induced alteration of bone cells and bone tissue by ion channels were included. Ion channels including TRP family channels, Ca release-activated Ca channels (CRACs), Piezo1/2 channels, purinergic receptors, NMDA receptors, voltage-sensitive calcium channels (VSCCs), TREK2 potassium channels, calcium- and voltage-dependent big conductance potassium (BK) channels, small conductance, calcium-activated potassium (SK) channels and epithelial sodium channels (ENaCs) present on bone cells and bone tissue participate in the mechanical regulation of bone development in addition to contributing to direct or indirect mechanotransduction such as altered membrane potential and ionic flux. Physiological (beneficial) mechanical stimulation could induce the anabolism of bone cells and bone tissue through ion channels, but abnormal (harmful) mechanical stimulation could also induce the catabolism of bone cells and bone tissue through ion channels. Functional expression of ion channels is vital for the mechanotransduction of bone cells. Mechanical activation (opening) of ion channels triggers ion influx and induces the activation of intracellular modulators that can influence bone metabolism. Therefore, mechanosensitive ion channels provide new insights into therapeutic targets for the treatment of bone-related diseases such as osteopenia and aseptic implant loosening.
Topics: Animals; Bone and Bones; Cell Line; Humans; Ion Channels; Mechanotransduction, Cellular; Receptors, Purinergic
PubMed: 34461086
DOI: 10.1016/j.abb.2021.109020 -
Journal of Dentistry Aug 2015This meta-analysis was performed to evaluate the efficacy of potassium nitrate and sodium fluoride as desensitizing agents during tooth bleaching treatment. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
This meta-analysis was performed to evaluate the efficacy of potassium nitrate and sodium fluoride as desensitizing agents during tooth bleaching treatment.
DATA, SOURCES AND STUDY SELECTION
An electronic systematic literature search was conducted in Cochrane Center Register of Controlled Trials, MEDLINE (PubMed) and EmBase in April, 2014 in English and without time restrictions. Study information extraction and methodological quality assessments were accomplished by two reviewers independently. Methodological quality was assessed by using the "Criteria for judging risk of bias in the 'Risk of bias' assessment tool". Dichotomous data was summarized by odds ratio (OR) with 95% confidence interval (CI) and continuous data was summarized by mean difference (MD) or standardised mean difference (SMD) with 95% confidence interval (CI). Statistical analyses were carried out by using Review Manager 5.2. For evaluation of percent of patients experiencing tooth sensitivity (POTS), the pooled OR of desensitizers vs. placebo was 0.45 (95% CI: 0.28-0.73, P=0.29). The pooled SMD of desensitizers vs. placebo was -0.47 (95% CI: -0.77 to -0.18, P=0.13) in evaluation of level of tooth sensitivity (LOTS). The results of shade evaluation remained inconsistent by evaluating subjective shade guide unit difference (ΔSGU or SGU) and objective colour difference (ΔE).
CONCLUSIONS
This meta-analysis was performed to evaluate the efficacy of desensitizing agents, potassium nitrate and sodium fluoride, for tooth bleaching treatments. Potassium nitrate and sodium fluoride reduce tooth sensitivity while no consistent conclusion of tooth colour change was found.
CLINICAL SIGNIFICANCE
Tooth sensitivity is a typical side effect associated with tooth bleaching procedures. Potassium nitrate and sodium fluoride are used widely to treat tooth sensitivity. This meta-analysis was performed to evaluate the efficacy of potassium nitrate and sodium fluoride as desensitizing agents during tooth bleaching treatment.
Topics: Dentin Desensitizing Agents; Humans; Nitrates; Placebos; Potassium Compounds; Sodium Fluoride; Tooth Bleaching; Tooth Bleaching Agents; Treatment Outcome
PubMed: 25913140
DOI: 10.1016/j.jdent.2015.03.015 -
The Cochrane Database of Systematic... Aug 2016The ideal intravenous fluid for kidney transplantation has not been defined, despite the common use of normal saline during the peri-operative period. The high chloride... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The ideal intravenous fluid for kidney transplantation has not been defined, despite the common use of normal saline during the peri-operative period. The high chloride content of normal saline is associated with an increased risk of hyperchloraemic metabolic acidosis, which may in turn increase the risk of hyperkalaemia and delayed graft function. Balanced electrolyte solutions have a lower chloride content which may decrease this risk and avoid the need for dialysis due to hyperkalaemia in the immediate post-transplant period. Randomised controlled trials (RCTs) addressing this issue have used biochemical outcomes to compare fluids and have been underpowered to address patient-centred outcomes such as delayed graft function.
OBJECTIVES
To examine the effect of lower-chloride solutions versus normal saline on delayed graft function, hyperkalaemia and acid-base status in kidney transplant recipients.
SEARCH METHODS
We searched the Cochrane Kidney and Transplant's Specialised Register to 26 November 2015 through contact with the Information Specialist using search terms relevant to this review.
SELECTION CRITERIA
RCTs of kidney transplant recipients that compared peri-operative intravenous lower-chloride solutions to normal saline were included.
DATA COLLECTION AND ANALYSIS
Two independent investigators assessed studies for eligibility and risk of bias. Data from individual studies were extracted using standardised forms and pooled according to a published protocol. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes.
MAIN RESULTS
Six studies (477 participants) were included in the review. All participants were adult kidney transplant recipients and 70% of participants underwent live-donor kidney transplantation. The overall risk of bias was low for selection bias and unclear for remaining domains. There was no difference in the risk of delayed graft function (3 studies, 298 participants: RR 1.03, 95% CI 0.62 to 1.70) or hyperkalaemia (2 studies, 199 participants: RR 0.48, 95% CI 0.04 to 6.10) for participants who received balanced electrolyte solutions compared to normal saline. Intraoperative balanced electrolyte solutions compared to normal saline were associated with higher blood pH (3 studies, 193 participants: MD 0.07, 95% CI 0.05 to 0.09), higher serum bicarbonate (3 studies, 215 participants: MD 3.02 mEq/L, 95% CI 2.00 to 4.05) and lower serum chloride (3 studies, 215 participants: MD -9.93 mmol/L, 95% CI -19.96 to 0.11). There were four cases of graft loss in the normal saline group and one in the balanced electrolyte solution group, and four cases of acute rejection in the normal saline group compared to two cases in the balanced electrolyte solution group.
AUTHORS' CONCLUSIONS
Balanced electrolyte solutions are associated with less hyperchloraemic metabolic acidosis compared to normal saline, however it remains uncertain whether lower-chloride solutions lead to improved graft outcomes compared to normal saline.
Topics: Adult; Delayed Graft Function; Gluconates; Humans; Hydrogen-Ion Concentration; Hyperkalemia; Infusions, Intravenous; Isotonic Solutions; Kidney; Kidney Transplantation; Magnesium Chloride; Potassium Chloride; Ringer's Solution; Sodium Acetate; Sodium Chloride; Solutions
PubMed: 27502170
DOI: 10.1002/14651858.CD010741.pub2 -
Medicine Sep 2018We sought to identify common ion channel single nucleotide polymorphisms (SNPs) associated with the occurrence of sudden cardiac death (SCD) to predict the incidence of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
We sought to identify common ion channel single nucleotide polymorphisms (SNPs) associated with the occurrence of sudden cardiac death (SCD) to predict the incidence of SCD in clinical settings.
METHODS
This study involved a systematic review and meta-analysis of ion channel SNPs and risk of SCD in adults. We searched public databases for studies published up to September 19, 2017. We examined relationships between SNPs in common ion channel genes and the incidence of SCD.
RESULTS
We collected data for 22 trials that included a total of 4149 patients who experienced SCD or had a high risk of SCD and assessed these data in our meta-analysis. An allelic model showed that rs11720524 in SCN5A clearly protected against SCD (odds ratio [OR]: 0.76; 95% confidence interval [95% CI]: 0.67-0.85; P < .001). Subgroup analysis showed that rs11720524 in SCN5A protected against SCD in Europeans and Caucasians but not in Koreans. The allelic model indicated that rs12296050 in KCNQ1 also had significant protective effects against SCD (OR: 0.85; 95% CI: 0.76-0.96; P = .007). Moreover, this model demonstrated that rs2283222 in KCNQ1 had a significant negative relationship with SCD (OR: 0.73; 95% CI: 0.62-0.85; P < .001). Rs12296050 in KCNQ1 protected against SCD in Koreans and Americans. Our results also showed that rs790896 in RYR2 was negatively associated with SCD in a dominant model (OR: 0.66; 95% CI: 0.45-0.97; P = .033).
CONCLUSIONS
Rs11720524 in SCN5A is negatively related to SCD in Europeans and Caucasians, and rs12296050 and rs2283222 in KCNQ1 and rs790896 in RYR2 clearly have protective effects against SCD.
Topics: Adult; Alleles; Asian People; Death, Sudden, Cardiac; Female; Humans; Incidence; Ion Channels; KCNQ1 Potassium Channel; Male; NAV1.5 Voltage-Gated Sodium Channel; Observational Studies as Topic; Polymorphism, Single Nucleotide; Predictive Value of Tests; Ryanodine Receptor Calcium Release Channel; White People
PubMed: 30235722
DOI: 10.1097/MD.0000000000012428 -
Clinical Neurology and Neurosurgery Jan 2021To conduct a systematic review of the available literature for primary research articles identifying potential gene mutations, polymorphisms and other molecular...
OBJECTIVE
To conduct a systematic review of the available literature for primary research articles identifying potential gene mutations, polymorphisms and other molecular regulatory mechanisms related to trigeminal neuralgia in order to identify the genetic and molecular models of primary trigeminal neuralgia currently being investigated.
METHODS
PubMed and Web of Science were systematically searched to identify primary research articles discussing genetic predictors of trigeminal neuralgia and neuropathic pain that were published prior to July 2020. This review was conducted according to PRISMA guidelines.
RESULTS
Out of the 333 articles originally identified, a total of 14 papers were selected for study inclusion. These articles included 5 human studies, 6 mouse studies and 3 rat studies. Four articles investigated sodium channels, 1 investigated a sodium channel and nerve growth factor receptor, 2 investigated potassium channels, 1 investigated calcium channels, 1 investigated the downstream regulatory element antagonist modulator protein, 1 investigated the dynorphin-kappa opioid receptor system, 1 investigated TRPA1, 1 investigated the Nrg1/ErbB3/ErbB2 signaling complex, 1 investigated a serotonin transporter and 1 investigated potassium channels, sodium channels, calcium channels, chloride channels, TRP channels and gap junctions.
CONCLUSION
Researchers have identified multiple genetic and molecular targets involved with potential pathophysiologies that have a relationship to the creation of trigeminal neuralgia. At this time, there does not seem to be clear causal frontrunner, demonstrating the possibility that genetic predisposition to trigeminal neuralgia may involve multiple genes and/or downstream products, such as ion channels.
Topics: Animals; Genetic Predisposition to Disease; Humans; Ion Channels; Neuralgia; Polymorphism, Genetic; Trigeminal Neuralgia
PubMed: 33338828
DOI: 10.1016/j.clineuro.2020.106397 -
International Journal of Molecular... Oct 2021The Epithelial Sodium Channel/Degenerin (ENaC/DEG) family is a superfamily of sodium-selective channels that play diverse and important physiological roles in a wide...
The Epithelial Sodium Channel/Degenerin (ENaC/DEG) family is a superfamily of sodium-selective channels that play diverse and important physiological roles in a wide variety of animal species. Despite their differences, they share a high homology in the pore region in which the ion discrimination takes place. Although ion selectivity has been studied for decades, the mechanisms underlying this selectivity for trimeric channels, and particularly for the ENaC/DEG family, are still poorly understood. This systematic review follows PRISMA guidelines and aims to determine the main components that govern ion selectivity in the ENaC/DEG family. In total, 27 papers from three online databases were included according to specific exclusion and inclusion criteria. It was found that the G/SxS selectivity filter (glycine/serine, non-conserved residue, serine) and other well conserved residues play a crucial role in ion selectivity. Depending on the ion type, residues with different properties are involved in ion permeability. For lithium against sodium, aromatic residues upstream of the selectivity filter seem to be important, whereas for sodium against potassium, negatively charged residues downstream of the selectivity filter seem to be important. This review provides new perspectives for further studies to unravel the mechanisms of ion selectivity.
Topics: Amiloride; Animals; Epithelial Sodium Channels; Humans; Ion Transport; Lithium; Molecular Dynamics Simulation; Mutagenesis, Site-Directed; Protein Structure, Quaternary; Sodium
PubMed: 34681656
DOI: 10.3390/ijms222010998