Placebo-controlled trial of essential fatty acid supplementation in atopic dermatitis

Herbal Medicine in Children and Adults With Atopic Dermatitis: A Systematic Review and Meta-Analysis

Herbal medicine is widely used for dermatological diseases, particularly atopic dermatitis. This study aims to systematically review existing literature on the efficacy of both topical and systemic herbal interventions for atopic dermatitis across various age groups. Conducting a comprehensive search on MEDLINE/PubMed, Scopus, and the Cochrane Central Register of Controlled Trials (Central) until April 12, 2023, only randomized controlled trials (RCTs) were included. The review is reported following the PRISMA guidelines and was conducted in accordance to Cochrane recommendations. Two authors independently extracted details, including demographics, medication, control/placebo groups, outcomes, adverse events, and results, with quality assessment using the Cochrane risk of bias tool 2.0. A meta-analysis, utilizing the random-effects model, was conducted, and publication bias was assessed through funnel plot inspection. The quality of evidence adhered to GRADE working group recommendations. The primary focus was evaluating atopic dermatitis or pruritus severity. The review encompassed 51 RCTs (3763 participants). Of these, 31 RCTs explored 19 distinct herbs and five complex remedies, whereas 20 RCTs (1088 participants) specifically investigated evening primrose oil (EPO). Herbs such as sunflower, licorice, figs, coconut, EPO, indigo naturalis, licorice, mauve, St. John's wort, and a combination of aloe vera and olive oil were found to have evidence of efficacy in the local treatment of atopic dermatitis. A meta-analysis on systemic used EPO, involving 13 RCTs, found no significant difference in atopic dermatitis severity compared with placebo (SMD: 0.14; 95% CI [-0.45; 0.73], 13 RCTs). In conclusion, this review provides a nuanced perspective on herbal substance efficacy for atopic dermatitis. While the EPO meta-analysis failed to show a discernible benefit beyond placebo, individual herbal preparations showed promising results in RCTs included in this review. Nevertheless, larger, methodologically rigorous studies are essential to establish evidence for herbal remedies in atopic dermatitis treatment.

Dietary Interventions in Atopic Dermatitis: A Comprehensive Scoping Review and Analysis

BACKGROUND

This scoping review aims to critically assess gaps in the current literature on atopic dermatitis (AD) by evaluating the overall effectiveness of dietary interventions. Through a comprehensive analysis that follows the Preferred Reporting Item for Systematic Review and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines, we conducted a thorough search on the Web of Science database in May 2023 using specific search strategies to identify all relevant studies on the research topic.

SUMMARY

A total of 104 full-text articles were included for review. Our synthesis identified seven notable categories of dietary interventions for AD, showcasing the diversity of interventions utilized. This includes vitamin supplementation, probiotic and prebiotic supplementation, dietary fat, biological compounds, foods from natural sources, major nutrients, and diet-related approaches. Further analyses stratified by targeted populations revealed a predominant focus on pediatrics, particularly in probiotic supplementation, and on adults, with an emphasis on vitamin D and E supplementation.

KEY MESSAGES

Despite most dietary interventions demonstrating overall effectiveness in improving AD severity and its subjective symptoms, several significant gaps were identified. There was a scarcity of studies on adults and whole-diet interventions, a prevalence of short-term interventions, heterogeneity in study outcomes, designs, and population, occasional disparity between statistical significance and clinical relevance, and a lack of a comprehensive multidisciplinary approach. Nonetheless, these findings offer valuable insights for future AD research, guiding additional evidence-driven dietary interventions and informing healthcare professionals, researchers, and individuals, advancing both understanding and management of AD.

The effect of Oenothera biennis (Evening primrose) oil on inflammatory diseases: a systematic review of clinical trials

BACKGROUND

Evening primrose oil (EPO), extracted from the seeds of Oenothera biennis, has gained attention for its therapeutic effects in various inflammatory conditions.

METHOD

We performed a systematic search in multiple databases and defined the inclusion criteria based on the following PICOs: P: Patients with a form of inflammatory condition, I: EPO, C: Placebo or other therapeutic interventions, O: changes in inflammatory markers or patients' symptoms; S: randomized controlled trials. The quality of the RCTs was evaluated using Cochrane's RoB tool.

RESULTS

Several conditions were investigated in the literature. In rheumatoid arthritis, mixed results were observed, with some studies reporting significant improvements in symptoms while others found no significant impact. EPO showed some results in diabetes mellitus, atopic eczema, menopausal hot flashes, and mastalgia. However, it did not demonstrate effectiveness in chronic hand dermatitis, tardive dyskinesia, psoriatic arthritis, cystic fibrosis, hepatitis B, premenstrual syndrome, contact lens-associated dry eyes, acne vulgaris, breast cyst, pre-eclampsia, psoriasis, or primary Sjogren's syndrome. Some results were reported from multiple sclerosis after EPO consumption. Studies in healthy volunteers indicated no significant effect of EPO on epidermal atrophy, nevertheless, positive effects on the skin regarding hydration and barrier function were achieved.

CONCLUSION

Some evidence regarding the potential benefits of EPO in inflammatory disorders were reported however caution is due to the limitations of the current survey. Overall, contemporary literature is highly heterogeneous and fails to provide strong recommendations regarding the efficacy of EPO on inflammatory disorders. Further high-quality studies are necessitated to draw more definite conclusions and establish O. biennis oil effectiveness as an assuring treatment option in alleviating inflammatory conditions.

Causal effects of fatty acids on atopic dermatitis: A Mendelian randomization study

Background

Some evidence suggests abnormalities in fatty acids in patients with atopic dermatitis (AD), and benefits of supplementation with these fatty acids have been reported. However, there is still substantial controversy on the correlation between fatty acids and AD. Therefore, the aim of this study was to determine whether fatty acid levels are causally related to AD using a Mendelian randomization approach.

Methods

We evaluated the data about the fatty acids levels and AD with various methods from Genome-Wide Association Study (GWAS). GWAS results were available both from European ancestry. Mendelian randomization methods were used to analysis the casual inference of fatty acids on AD. MR Egger and MR-PRESSO were used to determine pleiotropy and heterogeneity. Further analysis was conducted using instruments associated with the FADS genes to address mechanisms involved. We also used Multivariate MR (MVMR) to show the independent casual inference of omega-3 (n-3) fatty acids on AD.

Results

Mendelian randomization (MR) analysis suggests that n-3 fatty acid levels are associated with a lower risk of AD (n-3 OR_IVW: 0.92, 95% confidence interval [CI]: 0.87-0.98; p = 0.01). Moreover, docosahexaenoic acids (DHA) levels, which is a kind of long-chain, highly unsaturated omega-3 (n-3) fatty acid, and its higher level was associated with a lower risk of AD (DHA ORIVW: 0.91, 95% CI: 0.84-0.98; p = 0.02). We ran multivariable MR analysis while controlling for variables within the other types of fatty acids. The effect estimates agreed with the preliminary MR analysis indicating the effect of n-3 fatty acids levels on AD was robust. MR-egger suggest no significant pleiotropy and heterogeneity on genetic instrumental variants. Outliers-corrected MR analyses after controlling horizontal pleiotropy were still robust. The single-SNP analyses revealed that n-3 fatty acids are likely linked to a decreased risk of AD through FADS cluster, highlighting the significance of the FADS gene in the fatty acids synthesis pathway in the development of AD.

Conclusion

Our studies suggest that n-3 fatty acids may reduce the risk of AD. Risk prediction tools based on n-3 fatty acid levels may be valuable methods for improving AD screening and primary prevention. To reduce the risk of AD, individuals could enhance n-3 fatty acids intake through supplement or diet.

The Influence of Dietary Fatty Acids on Immune Responses

Diet-derived fatty acids (FAs) are essential sources of energy and fundamental structural components of cells. They also play important roles in the modulation of immune responses in health and disease. Saturated and unsaturated FAs influence the effector and regulatory functions of innate and adaptive immune cells by changing membrane composition and fluidity and by acting through specific receptors. Impaired balance of saturated/unsaturated FAs, as well as n-6/n-3 polyunsaturated FAs has significant consequences on immune system homeostasis, contributing to the development of many allergic, autoimmune, and metabolic diseases. In this paper, we discuss up-to-date knowledge and the clinical relevance of the influence of dietary FAs on the biology, homeostasis, and functions of epithelial cells, macrophages, dendritic cells, neutrophils, innate lymphoid cells, T cells and B cells. Additionally, we review the effects of dietary FAs on the pathogenesis of many diseases, including asthma, allergic rhinitis, food allergy, atopic dermatitis, rheumatoid arthritis, multiple sclerosis as well as type 1 and 2 diabetes.

EAACI position paper: Influence of dietary fatty acids on asthma, food allergy, and atopic dermatitis

The prevalence of allergic diseases such as allergic rhinitis, asthma, food allergy, and atopic dermatitis has increased dramatically during the last decades, which is associated with altered environmental exposures and lifestyle practices. The purpose of this review was to highlight the potential role for dietary fatty acids, in the prevention and management of these disorders. In addition to their nutritive value, fatty acids have important immunoregulatory effects. Fatty acid-associated biological mechanisms, human epidemiology, and intervention studies are summarized in this review. The influence of genetics and the microbiome on fatty acid metabolism is also discussed. Despite critical gaps in our current knowledge, it is increasingly apparent that dietary intake of fatty acids may influence the development of inflammatory and tolerogenic immune responses. However, the lack of standardized formats (ie, food versus supplement) and standardized doses, and frequently a lack of prestudy serum fatty acid level assessments in clinical studies significantly limit our ability to compare allergy outcomes across studies and to provide clear recommendations at this time. Future studies must address these limitations and individualized medical approaches should consider the inclusion of specific dietary factors for the prevention and management of asthma, food allergy, and atopic dermatitis.

Effect of Evening Primrose Oil on Korean Patients With Mild Atopic Dermatitis: A Randomized, Double-Blinded, Placebo-Controlled Clinical Study

Background

Atopic dermatitis (AD) is related to a deficiency of delta-6-desaturase, an enzyme responsible for converting linoleic acid to gamma-linolenic acid (GLA). Evening primrose oil (EPO) as a source of GLA has been of interest in the management of AD.

Objective

The aim of this randomized, double-blinded, placebo-controlled clinical study is to evaluate the efficacy and safety of EPO in Korean patients with AD.

Methods

Fifty mild AD patients with an Eczema Area Severity Index (EASI) score of 10 or less were enrolled and randomly divided into two groups. The first group received an oval unmarked capsule containing 450 mg of EPO (40 mg of GLA) per capsule, while placebo capsules identical in appearance and containing 450 mg of soybean oil were given to the other group. Treatment continued for a period of four months. EASI scores, transepidermal water loss (TEWL), and skin hydration were evaluated in all the AD patients at the baseline, and in months 1, 2, 3, and 4 of the study.

Results

At the end of month 4, the patients of the EPO group showed a significant improvement in the EASI score (p=0.040), whereas the patients of the placebo group did not. There was a significant difference in the EASI score between the EPO and placebo groups (p=0.010). Although not statistically significant, the TEWL and skin hydration also slightly improved in the EPO patients group.

Conclusion

We suggest that EPO is a safe and effective medicine for Korean patients with mild AD.

Therapeutic Benefits of Natural Ingredients for Atopic Dermatitis

Although a variety of regimens are available for the treatment of atopic dermatitis (AD), severe adverse reactions and unpopular costs often limit their usage. In contrast, certain inexpensive, naturally-occurring ingredients are proven effective for AD with fewer side effects. The beneficial effects of these ingredients can be attributed to inhibition of cytokine and chemokine expression, IgE production, inflammatory cell infiltration, histamine release, and/or the enhancement of epidermal permeability barrier function. Since herbal medicines are widely available, inexpensive and generally safe, they could be valuable alternatives for the treatment of AD, particularly for those patients who are not suitable for the utilization of immune modulators. In this review, we summarize the therapeutic benefits of natural ingredients for the treatment of AD and the mechanisms of their actions.

Complementary and Alternative Medicine for Atopic Dermatitis: An Evidence-Based Review

BACKGROUND

Complementary and alternative interventions are becoming increasingly utilized as adjuncts to conventional treatment of atopic dermatitis (AD). While the number of studies continues to grow, the vastness of the subject coupled with the relatively poor quality and small size of the studies limit their usefulness to clinicians.

PURPOSE

Our aim was to comprehensively review randomized controlled trials (RCTs) of complementary and alternative therapies for AD.

METHODS

Searches were performed on PubMed, the Cochrane Central Register of Controlled Trials, EMBASE, and the Global Resource for EczemA Trial (GREAT) databases, focusing on RCTs of alternative or complementary AD therapies, with a sample size of ≥10, through March 2015 and limited to the English language. A total of 70 manuscripts met the inclusion criteria and were included in the final analysis.

RESULTS

There is at least some level I evidence to support the use of acupuncture and acupressure, stress-reducing techniques such as hypnosis, massage, and biofeedback, balneotherapy, herbal preparations (with many important caveats), certain botanical oils, oral evening primrose oil, vitamin D supplementation, and topical vitamin B₁₂. Many other therapies either have sufficient data to suggest that they are ineffective, or simply do not have enough evidence to formulate a verdict.

CONCLUSIONS

Careful review of the literature reveals several promising therapies in this domain; such findings may help direct further research that is necessary to bolster clinical recommendations for alternative or complementary treatments of AD.

Electrical conductance: a controversial parameter in the evaluation of emollients in atopic dermatitis

BACKGROUND/AIMS

Essential fatty acids are important in maintaining skin function and their deficiency is associated with scali-ness and increased transepidermal water loss (TEWL). This can be one of the pathogenic processes implicated in atopic dermatitis (AD). Several studies have assessed the value of essential fatty acid-enriched diets in AD but the benefits of topical γ-lino-lenic acid (GLA) therapy have been less well evaluated. The aims of this study were: a) to compare the effects of GLA-con-taining emollients and classical emollients, regarding clinical benefits, cutaneous hydration (by a conductance method) and TEWL; b) to assess the clinical relevance of these two biomet-rical methods (conductance and TEWL).

METHODS

Twenty-three AD children were randomised into four groups, to compare three emollients containing GLA in different concentrations and one classical emollient. They were evaluated in eight visits for 12 weeks, using a clinical score and measurements of TEWL with the Tewameter™ and of cutaneous hydration with the Nova™.

RESULTS

Kruskal-Wallis statistical analysis showed significant differences in cutaneous hydration (P<0.05) between each of the three treatment groups and the control group. TEWL and clinical scores did not show statistically significant differences. During the study no children from the GLA groups developed eczematous lesions versus two children from the non-GLA group.

CONCLUSIONS

Discrepancies between conductance and TEWL measurements may represent false positive results of the former method due to electrical phenomena related to polarity of the GLA molecule or of other elements in the formulations. However, some differences in clinical evolution between the GLA and non-GLA groups require further studies to assess the possible additional benefits of topical emollients containing GLA.

Circulating CD4(+) CD25(high) FoxP3(+) T-regulatory cells in patients with atopic dermatitis after narrowband-ultraviolet B phototherapy

BACKGROUND

Previous studies showed controversial results regarding CD4(+) CD25(high) FoxP3(+) T-regulatory cells (Tregs) in atopic dermatitis (AD) and effect of therapy.

METHODS

Circulating CD4(+) CD25(high) FoxP3(+) Tregs were assessed by flow cytometry in 20 controls and 20 patients with AD at baseline and after narrowband ultraviolet B with assessment of disease severity.

RESULTS

Patients showed higher pretreatment T-effector cells (Teffs) (%) and lower pretreatment Tregs FoxP3 expression% than controls (P = 0.003 and 0.01, respectively). Mild AD showed a lower Tregs/Teffs ratio compared to controls (P = 0.013), while moderate group showed higher Teffs%, and lower Tregs FoxP3 expression% and Tregs/Teffs compared to controls (P = 0.016, 0.007, and 0.009 respectively). The severe group had higher Tregs% and Teffs%, yet with a lower Tregs FoxP3 expression% compared to controls (P < 0.001, P = 0.043, P = 0.044, respectively). There was significant reduction of severity after narrowband ultraviolet B (P = 0.007), with overall significant elevation of Tregs FoxP3 expression% in patients (P = 0.004). All patients' post-treatment laboratory findings were statistically matched to each other and to controls whatever their previous severity or therapeutic response. The improvement of severity score correlated with the change in both Tregs% and Tregs/Teffs.

CONCLUSIONS

Significant reduction in AD disease severity is correlated with the change in Tregs% and Tregs/Teffs.

Contributing factors to the development of childhood asthma: working toward risk minimization

Asthma is the most common chronic disease in childhood, and considerable research has been undertaken to find ways to prevent its development and reduce its prevalence. For such interventions to be successful, risk factors for asthma emergence should be identified and clearly defined. Data are robust for some of them, including atopy, viral infections and exposure to airborne irritants, whereas it is less conclusive for others, such as aeroallergen exposure and bacterial infections. Several interventions for asthma prevention, including avoidance and pharmacotherapy, have been attempted. However, most of them have furnished equivocal results. Various issues hinder the establishment of risk factors for asthma development and reduce the effectiveness of interventions, including the complexity of the disease and the fluidity of the developing systems in childhood. In this review, we revisit the evidence on pediatric asthma risk factors and prevention and discuss issues that perplex this field.

Dihomo-γ-linolenic acid prevents the development of atopic dermatitis through prostaglandin D1 production in NC/Tnd mice

BACKGROUND

Atopic dermatitis (AD) is a chronic and relapsing skin disorder with pruritic skin symptoms. We previously reported that dihomo-γ-linolenic acid (DGLA) prevented the development of AD in NC/Tnd mice, though the mechanism remained unclear.

OBJECTIVE

We attempted to investigate the mechanism of preventive effect of DGLA on AD development in NC/Tnd mice.

METHODS

The clinical outcomes of NC/Tnd mice that were given diets containing DGLA, arachidonic acid, or eicosapentaenoic acid were compared. Lipid mediator contents in the skin in each group were also quantified. In addition, release of lipid mediators from RBL-2H3 mast cells treated with either DGLA or prostaglandin D1 (PGD1) was measured. Furthermore, effect of PGD1 on gene expression of thymic stromal lymphopoietin (TSLP) in PAM212 keratinocyte cells was determined.

RESULTS

Only DGLA containing diet suppressed the development of dermatitis in vivo. By quantifying the 20-carbon fatty acid-derived eicosanoids in the skin, the application of DGLA was found to upregulate PGD1, which correlated with a better outcome in NC/Tnd mice. Moreover, we confirmed that mast cells produced PGD1 after DGLA exposure, thereby exerting a suppressive effect on immunoglobulin E-mediated degranulation. PGD1 also suppressed gene expression of TSLP in keratinocytes.

CONCLUSION

These results suggest that oral administration of DGLA causes preventive effects on AD development in NC/Tnd mice by regulating the PGD1 supply.

Guidelines of care for the management of atopic dermatitis: Section 4. Prevention of disease flares and use of adjunctive therapies and approaches

Atopic dermatitis is a common, chronic inflammatory dermatosis that can affect all age groups. This evidence-based guideline addresses important clinical questions that arise in its management. In this final section, treatments for flare prevention and adjunctive and complementary therapies and approaches are reviewed. Suggestions on use are given based on available evidence.

Increased FADS2-Derived n-6 PUFAs and Reduced n-3 PUFAs in Plasma of Atopic Dermatitis Patients

Fatty acid concentrations, in particular n-3 and n-6 polyunsaturated fatty acids (PUFAs), have been described to be dysregulated in atopic dermatitis (AD) patients. The role of genetic polymorphisms of fatty acid enzymes in AD is controversial. We determined in a Hungarian cohort of healthy volunteers (n = 20) and AD patients (n = 20) triglyceride-, sterol- and phospholipid-bound fatty acids in the plasma, mRNA expression of fatty acid desaturase 2 (FADS2) and stearoyl-coenzyme A desaturase 1 in peripheral blood mononuclear cells (PBMCs) and FADS2 concentrations in plasma. We observed higher levels of monounsaturated fatty acids, 16:1 versus 16:0 ratios in phospholipids, triglycerides and sterol esters in patients compared to healthy subjects. In addition higher levels of the FADS2-derived n-6 PUFAs &#947;-linolenic acid and dihomo-&#947;-linolenic acid were observed in PBMCs of patients as well as lower levels of n-3 PUFAs. We conclude that the increased expression of FADS2 in PBMCs, as a representative tissue accessible from human blood of AD patients, might be responsible for higher levels of FADS2-derived n-6 PUFAs and lower n-3 PUFA levels in patients.

Oral evening primrose oil and borage oil for eczema

BACKGROUND

Eczema is a chronic inflammatory skin condition, which usually develops in early childhood. Many children outgrow this disorder as they reach secondary school age, and although It may improve with age, there is no cure. Constant itch makes life uncomfortable for those with this condition, no matter what age they are, so it may have a significant effect on a person's quality of life. Its prevalence seems to be increasing as populations move from rural locations to cities. Some people, who do not see an adequate improvement or fear side-effects of conventional medical products, try complementary alternatives to conventional treatment. This is a review of evening primrose oil (EPO) and borage oil (BO) taken orally (by mouth); these have been thought to be beneficial because of their gamma-linolenic acid content.

OBJECTIVES

To assess the effects of oral evening primrose oil or borage oil for treating the symptoms of atopic eczema.

SEARCH METHODS

We searched the following databases up to August 2012: Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library, MEDLINE (from 1946), EMBASE (from 1974), AMED (from 1985), and LILACS (from 1982). We also searched online trials registers and checked the bibliographies of included studies for further references to relevant trials. We corresponded with trial investigators and pharmaceutical companies to try to identify unpublished and ongoing trials. We performed a separate search for adverse effects of evening primrose oil and borage oil in November 2011.

SELECTION CRITERIA

All randomised controlled, parallel, or cross-over trials investigating oral intake of evening primrose oil or borage oil for eczema.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied eligibility criteria, assessed risk of bias, and extracted data. We pooled dichotomous outcomes using risk ratios (RR), and continuous outcomes using the mean difference (MD). Where possible, we pooled study results using random-effects meta-analysis and tested statistical heterogeneity using both the Chi(²) test and the I(²) statistic test. We presented results using forest plots with 95% confidence intervals (CI).

MAIN RESULTS

A total of 27 studies (1596 participants) met the inclusion criteria: 19 studies assessed evening primrose oil, and 8 studies assessed borage oil. For EPO, a meta-analysis of results from 7 studies showed that EPO failed to significantly increase improvement in global eczema symptoms as reported by participants on a visual analogue scale of 0 to 100 (MD -2.22, 95% CI -10.48 to 6.04, 176 participants, 7 trials) and a visual analogue scale of 0 to 100 for medical doctors (MD -3.26, 95% CI -6.96 to 0.45, 289 participants, 8 trials) compared to the placebo group.Treatment with BO also failed to significantly improve global eczema symptoms compared to placebo treatment as reported by both participants and medical doctors, although we could not conduct a meta-analysis as studies reported results in different ways. With regard to the risk of bias, the majority of studies were of low risk of bias; we judged 67% of the included studies as having low risk of bias for random sequence generation; 44%, for allocation concealment; 59%, for blinding; and 37%, for other biases.

IMPLICATIONS FOR PRACTICE

Oral borage oil and evening primrose oil lack effect on eczema; improvement was similar to respective placebos used in trials. Oral BO and EPO are not effective treatments for eczema.In these studies, along with the placebos, EPO and BO have the same, fairly common, mild, transient adverse effects, which are mainly gastrointestinal.The short-term studies included here do not examine possible adverse effects of long-term use of EPO or BO. A case report warned that if EPO is taken for a prolonged period of time (more than one year), there is a potential risk of inflammation, thrombosis, and immunosuppression; another study found that EPO may increase bleeding for people on Coumadin® (warfarin) medication.

IMPLICATIONS FOR RESEARCH

Noting that the confidence intervals between active and placebo treatment are narrow, to exclude the possibility of any clinically useful difference, we concluded that further studies on EPO or BO for eczema would be hard to justify.This review does not provide information about long-term use of these products.

Inhibitory effects of Oenothera biennis (evening primrose) seed extract on Streptococcus mutans and S. mutans-induced dental caries in rats

BACKGROUND

Oenothera biennis (evening primrose) seed extract (OBSE) is known to contain polyphenols, which may possess antioxidant activities. Polyphenols extracted from several plants are reported to exhibit cariostatic activities by inhibiting mutans streptococcus growth and glucosyltransferase activities. The purpose of the present study was to examine the inhibitory effects of OBSE on the development of dental caries, both in vitro and in vivo.

METHODS

OBSE was investigated for its inhibitory effects on cellular aggregation, hydrophobicity, sucrose-dependent adherence and insoluble glucan synthesis. Furthermore, biofilm formation was examined in the presence of OBSE, using confocal microscopic imaging. An animal experiment was also performed to examine the in vivo effects.

RESULTS

OBSE induced a strong aggregation of Streptococcus mutans MT8148 cells, while cell surface hydrophobicity was decreased by approximately 90% at a concentration of 0.25 mg/ml. The sucrose-dependent adherence of the MT8148 cells was also reduced by addition of OBSE, with a reduction rate of 73% seen at a concentration of 1.00 mg/ml. Additionally, confocal microscopic observations revealed the biofilm development phase to be remarkably changed in the presence of OBSE. Furthermore, insoluble glucan synthesis was significantly reduced when OBSE was present at concentrations greater than 0.03 mg/ml. In an animal experiment, the caries scores in rats given OBSE (0.05 mg/ml in drinking water) were significantly lower than those in rats given water without OBSE.

CONCLUSION

Our results indicate that OBSE has inhibitory activity on dental caries.

The Self-administered Eczema Area and Severity Index in children with moderate to severe atopic dermatitis: better estimation of AD body surface area than severity

The Self-Administered Eczema Area and Severity Index (SA-EASI) is one of the few patient based atopic dermatitis (AD) disease activity scores and was found to be highly correlated with the EASI. Correlation with other frequently used scoring methods has not been investigated. The aim of this study was to evaluate the relation of the SA-EASI with two physician-based disease activity scores (objective SCORAD and SASSAD score) and with a serum marker for AD (Thymus and Activation-Regulated Cytokine [TARC]) in children with AD. Sixty children with moderate to severe AD were included. The SA-EASI was completed by caregivers, and the objective SCORAD and SASSAD scores were measured successively on the same day by a trained investigator. Blood for serum TARC measurement was drawn. The correlation between the SA-EASI and the objective SCORAD was high (ρ = 0.61, p = <0.001), mainly based on high correlation between the body surface area (BSA) measurements of both scores (ρ = 0.50, p = <0.001). The correlation with the SASSAD score (only severity measurement) was 0.43 (p = <0.001). The correlation with serum TARC levels was 0.46; p = <0.001, mainly based on the BSA score of the SA-EASI (ρ = 0.42, p = <0.001). Parents may have more difficulty in scoring severity of AD than scoring BSA involved. Educating parents in severity scoring of AD may improve agreement of the SA-EASI and the objective SCORAD, TARC, and SASSAD score. Additional use of the SA-EASI in routine clinical practice or in trials may then facilitate more frequent but still accurate assessment of AD.

What are the best outcome measurements for atopic eczema? A systematic review

BACKGROUND

Valid and reliable outcome measurements are a prerequisite for evidence-based practice. The comparative validity and reliability of outcome measurements for assessing atopic eczema (AE) severity is unclear.

OBJECTIVE

We sought to assess the validity, reliability, sensitivity to change, and ease of use of outcome measurements for AE. We also sought to give recommendations on which outcomes to use in clinical research and for clinical monitoring.

METHODS

We performed a systematic review and survey of clinical experts and patients.

RESULTS

Twenty published outcome measurements were identified. There is evidence of adequate construct validity for 3 measurements (Severity Scoring of Atopic Dermatitis index [SCORAD], Eczema Area and Severity Index [EASI], and Three Item Severity Score), adequate internal consistency of 1 scale (Patient-oriented Eczema Measure [POEM]), adequate interobserver reliability of 5 measurements (Basic Clinical Scoring System; Nottingham Eczema Severity Score; Objective Severity Assessment of Atopic Dermatitis; Six Area, Six Sign Atopic Dermatitis severity score; and SCORAD), adequate test-retest reliability of 1 scale (POEM), and adequate sensitivity to change of 3 measurements (EASI, SCORAD, and Investigators' Global Atopic Dermatitis Assessment). Most outcome measurements have adequate content validity, as assessed by patients and experts. Data on the time to perform the assessment was identified for 8 outcome measurements. Only SCORAD, EASI, and POEM have been tested sufficiently and performed adequately.

CONCLUSION

There are too many published outcome measures for AE. Most have not been tested properly or perform adequately when tested, and their continued use hampers scientific communication.

CLINICAL IMPLICATIONS

Only SCORAD, EASI, and POEM currently perform adequately. These scales should be used in future studies.

Quantitative analysis of anti-inflammatory and radical scavenging triterpenoid esters in evening primrose seeds

Lipophilic triterpenoidal esters with radical scavenging and cyclooxygenase inhibitory properties were recently found in cold-pressed, nonraffinated evening primrose oil (EPO). A quantitative assay for the analysis of 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid in evening primrose seeds was developed and validated. Extraction efficiency >99% was achieved by means of pressurized liquid extraction with two extraction cycles and 80% (v/v) ethanol at 120 degrees C. Analysis of esters was by normal-phase high-performance liquid chromatography on a Diol column and hexane/ethyl acetate (containing 0.1% formic acid) (65:35) as the eluent. The analytes were determined without further prepurification. Seeds from defined cultures of Oenothera biennis, Oenothera lamarckiana, and Oenothera ammophila, grown under identical conditions, were analyzed. The cultures originated from seeds from eight collections in the wild and from selections from five cultivars. The content of total triterpenoidal esters in seeds varied between 1.34 and 2.78 mg/g. Three types of qualitative patterns were observed for the triterpenoidal esters. The influence of different harvest times and plant treatments was studied with the cultivar Anothera. Variations between 1.5 and 2.3 mg/g were found.

Open trial of supplements of omega 3 and 6 fatty acids, vitamins and minerals in atopic dermatitis

OBJECTIVE

To investigate whether dietary supplementation with polyunsaturated fatty acids (PUFA) of the omega 3 series (n-3 PUFA: 18:3, n-3; 20:5, n-3; and 22:6, n-3), the omega 6 series (n-6 PUFA: 18:3, n-6), vitamins and minerals have a clinical effect on atopic dermatitis.

METHODS

A total of 19 patients aged 17-43 years with moderate to severe atopic dermatitis participated in an open trial of high oral doses of n-3 and n-6 PUFA in dry form (powder) or omega 3,6,9 fatty acid capsules, vitamin E tablets (d-alpha-tocopherol), zinc solution or tablets, and multivitamin capsules daily for 16 weeks.

RESULTS

The mean SCORAD improved in 14 of 17 patients by more than 50% after 8 weeks and 16 weeks of treatment (p<0.01 and p<0.001, respectively).

CONCLUSION

The open nature of this trial and the small number of subjects are major limitations of this study. The possible role of dietary omega 3 and 6 fatty acids in the treatment of atopic dermatitis should be tested more extensively in a double-blind trial using high doses of antioxidants combined with PUFA.

Treatment of atopic dermatitis with herbal combination of Eleutherococcus, Achillea millefolium, and Lamium album has no advantage over placebo: A double blind, placebo-controlled, randomized trial

OBJECTIVE

To test the efficacy of tri-herbal combination on atopic dermatitis in a randomized, placebo-controlled trial.

METHODS

Forty-nine patients were included for 2 weeks of treatment. Patients were followed until week 8.

RESULTS

The response to the real medication was significant in objective and subjective parameters. Patients maintained partial remission until the end of follow-up. The placebo-treated group had a similar response without a significant difference.

CONCLUSIONS

Treatment with tri-herbal combination for atopic dermatitis does not differ from treatment with placebo.

Oral essential fatty acid supplementation in atopic dermatitis-a meta-analysis of placebo-controlled trials

BACKGROUND

Essential fatty acids are components of cell membranes and precursors of immunomodulating factors that may play a role in the inflammatory and immunological pathogenesis of atopic dermatitis. Trials of supplementation with essential fatty acids (EFA) to alleviate atopic dermatitis (AD) have given inconsistent results.

OBJECTIVES

To summarize and quantify the results of placebo-controlled trials with EFA for AD.

DESIGN

Publications of clinical trials were searched in a systematic way and the study characteristics assessed independently by three assessors. Trials were selected for inclusion in the meta-analysis when they had included a placebo group and when the outcome measure included the severity of AD. The pooled effect sizes of improvement of the overall severity of AD were calculated by random effects meta-analysis. The dependence of the results on study characteristics was studied using meta-regression analysis.

RESULTS

We identified 34 publications of controlled trials in AD up to April 2002. Nineteen trials of gamma-linolenic acid (GLA) and five trials of fish oil matched our inclusion criterion of placebo-controlled trial. The effect size of GLA supplementation on the improvement of the overall severity of AD could be calculated from 11 of these trials. The pooled effect size was 0.15 [95% confidence limits (CL) - 0.02, 0.32]. The effect size of fish oil supplementation, calculated from three trials was - 0.01 (95% CL - 0.37, 0.30). For component subscales such as itch, scaling and lichenification, EFA supplementation showed no benefit. The study characteristics showed no detectable influence on the overall result.

CONCLUSIONS

Supplementation with EFA has no clinically relevant effect on the severity of AD.

N-3 polyunsaturated fatty acids and allergic disease

PURPOSE OF REVIEW

With escalating rates of allergic disease, it is vital to explore novel causal pathways. This review examines the evidence for a potential role of changing dietary intake of omega-3 polyunsaturated fatty acids in the development, treatment and prevention of allergic diseases.

RECENT FINDINGS

Although it is difficult to determine the contribution of altered (decreased) dietary intake of omega-3 polyunsaturated fatty acids to the recent rise in the incidence of allergic disease, there is growing evidence that these nutrients have antiinflammatory properties and may modulate immune responses. These fatty acids have few side effects, and may be of some benefit in established allergic diseases (such as asthma and atopic dermatitis), although these effects are not strong. Because of this limited efficacy in established disease, the focus has shifted to the potential benefits of these immune modulators in earlier life for disease prevention. Two recent preliminary reports in infants suggest that dietary omega-3 polyunsaturated fatty acid supplements in pregnancy or in the early postnatal period could have immunomodulatory properties and associated clinical effects, although more studies are now needed. Novel synthetic polyunsaturated fatty acids with more potent and selective antiinflammatory effects may also provide safe therapeutic and preventive strategies in the future.

SUMMARY

Dietary factors are important but still under-explored candidates in the search for environmental strategies to reduce the enormous impact of allergic diseases in modernized societies. There is an ongoing need for further research into the role of omega-3 polyunsaturated fatty acids in allergic disease, particularly in early life before atopy is established.

Complementary therapy for atopic eczema and other allergic skin diseases

Atopic eczema is one of the most common chronic inflammatory skin diseases, with a prevalence of at least 10% in children and 0.5-1% in adults. The disease shows a drastically increasing tendency. This article provides an overview of the pathophysiology, pathomechanisms, prevention, and treatment of atopic eczema. We present a therapeutic concept that integrates all aspects of the complex pathophysiology that is a prerequisite for individualized and successful treatment. This is based on intervention in the pathophysiology of atopic eczema and elimination of exogenous provocation factors. Particular attention is given to unconventional therapy options such as phytotherapy, which are attracting patients in many countries, and possible effects, side effects, and interactions with other drugs are discussed.

Efficacy and tolerability of borage oil in adults and children with atopic eczema: randomised, double blind, placebo controlled, parallel group trial

OBJECTIVE

To study the efficacy and tolerability of borage oil, which contains a high concentration of gamma linolenic acid, in children and adults with atopic eczema.

DESIGN

Single centre, randomised, double blind, placebo controlled, parallel group trial.

SETTING

Acute district general hospital in Nuneaton, England.

PARTICIPANTS

151 patients, of whom 11 failed to return for assessment, leaving an evaluable population of 140 (including 69 children).

INTERVENTION

Adults received four capsules of borage oil twice daily (920 mg gamma linolenic acid), and children received two capsules twice daily, for 12 weeks.

MAIN OUTCOME MEASURES

Change in total sign score at 12 weeks measured with the six area, six sign, atopic dermatitis (SASSAD) score (primary endpoint); symptom scores, assessed on visual analogue scales; topical corticosteroid requirement, assessed on a five point scale; global assessment of response by participants; adverse events and tolerability.

RESULTS

The mean SASSAD score fell from 30 to 27 in the borage oil group and from 28 to 23 in the placebo group. The difference between the mean improvements in the two groups was 1.4 (95% confidence interval -2.2 to 5.0) points in favour of placebo (P = 0.45). No significant differences occurred between treatment groups in the other assessments. Subset analysis of adults and children did not indicate any difference in response. The treatments were well tolerated.

CONCLUSION

Gamma linolenic acid is not beneficial in atopic dermatitis.

Complementary/alternative medicine in dermatology: evidence-assessed efficacy of two diseases and two treatments

The objective of this article is to provide a brief, but critical, overview of the evidence related to complementary/alternative medicine (CAM) use, and to offer valid and useful information for dermatologists in clinical practice. Systematic literature searches were conducted on these databases: Medline, EMBASE, The Cochrane Library, CISCOM and AMED (until October 2000). Where appropriate, the evaluation of the published literature was based on systematic reviews and randomized controlled trials. After scanning the literature it was decided to focus on a selection of two conditions (atopic dermatitis and chronic venous insufficiency) and two treatment modalities (aloe vera gel and tea tree oil). Data for the life-time prevalence of CAM use by patients with dermatological disease ranges between 35 to 69%. The most popular modalities include herablism and (other) dietary supplements, while atopic dermatitis is one of the conditions most frequently treated with CAM. For patients with atopic dermatitis the evidence relates to autogenic training, hypnotherapy, diet, herbal medicine, and dietary supplements. Compelling evidence of effectiveness exists for none of these therapies. However, some promising data have been reported for those with a psychological component: autogenic training, biofeedback and hypnotherapy. For chronic venous insufficiency there is relatively convincing evidence for the effectiveness of oral horse chestnut seed extract. The data for aloe vera gel and tea tree oil indicate that for neither is there compelling evidence of effectiveness. The use of CAM treatments is not free of risk; direct and indirect risks associated with CAM must be considered.

Effects of n-3 polyunsaturated fatty acids on dermatitis in NC/Nga mice

The administration of n-3 polyunsaturated fatty acids (PUFAs) is known to be effective against allergic diseases by suppressing the production of eicosanoids derived from arachidonic acid. To investigate the mechanisms and efficacy of n-3 PUFA treatment in patients with atopic dermatitis (AD), we administered four different formulas of alpha-linolenic acid for 6 weeks in an AD model using NC/Nga mice. According to the doses of alpha-linolenic acid given, the levels of alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid in the red blood cell membranes increased while the levels of linoleic acid and arachidonic acid decreased. However, there was no significant difference among the four dose groups in clinical skin severity score, histopathological findings of skin lesions, or levels of total plasma IgE. Moreover, there was no significant difference in the production of leukotriene B(4) and Leukotriene C(4) from skin lesions after stimulation with A23187 among the groups, although the production of prostaglandin E(2) (PGE(2)) was significantly reduced and skin blood flow in the ear was significantly higher in the group given the highest dose of alpha-linolenic acid. Our results suggest that the administration of alpha-linolenic acid can change the fatty acid composition, PGE(2) production, and skin blood flow but may not prevent the development of dermatitis in NC/Nga mice.

The ACVD task force on canine atopic dermatitis (XXIII): are essential fatty acids effective?

Essential fatty acids (EFAs) exhibit the potential to affect allergic inflammation through the modulation of prostaglandin and leukotriene production, the inhibition of cellular activation and cytokine secretion as well as the alteration of the composition and function of the epidermal lipid barrier. Because of these multi-faceted effects, EFA have been proposed for treatment of canine atopic dermatitis (AD) since 1987. To date, more than 20 trials have been performed, reporting the efficacy of either oral EFA supplements or EFA-rich diets. Unfortunately, most of these studies were found to exhibit one or more of the following deficiencies: heterogeneity of diagnoses used as inclusion criteria, short duration of supplementation, lack of randomization of treatment allocation, lack of blinding of investigators and/or owners, lack of placebo or active controls, lack of documentation of plasma or skin EFA profiles during supplementation, as well as lack of standardization of the basal diets or supplements which could have provided additional EFA. Consequently, there is presently insufficient evidence to recommend for or against the use of EFA to control clinical signs of canine AD. Evidence of efficacy must await the performance of blinded, randomized and controlled trials of at least 3 months duration in which diets are identical for all of study subjects. In these trials, clinical efficacy should be evaluated in relation to plasma and cutaneous EFA treatment-induced alterations.

Polyunsaturated n-3 fatty acids and the development of atopic disease

The relationship between polyunsaturated longchain fatty acids and atopy has been discussed for decades. Higher levels of the essential fatty acids linoleic acid and alpha-linolenic acid and lower levels of their longer metabolites in plasma phospholipids of atopic as compared to nonatopic individuals have been reported by several, but not all, studies. Largely similar findings have been reported in studies of cell membranes from immunological cells from atopics and non-atopics despite differences in methodology, study groups, and definitions of atopy. An imbalance in the metabolism of the n-6 fatty acids, particularly arachidonic acid and dihomo-gamma-linolenic acid, leading to an inappropriate synthesis of prostaglandin (PG) E2 and PGE1 was hypothesized early on but has not been corroborated. The fatty acid composition of human milk is dependent on the time of lactation not only during a breast meal but also the time of the day and the period of lactation. This explains the discrepancies in reported findings regarding the relationship between milk fatty acids and atopic disease in the mother. Prospective studies show disturbances in both the n-6 and n-3 fatty acid composition between milk from atopic and nonatopic mothers. Only the composition of long-chain polyunsaturated n-3 fatty acids was related to atopic development in the children, however. A relationship between lower levels of n-3 fatty acids, particularly eicosapentaenoic acid (20:5 n-3), and early development of atopic disease is hypothesized.

Nutritional skin care: health effects of micronutrients and fatty acids

Human skin is continuously exposed to internal and external influences that may alter its condition and functioning. As a consequence, the skin may undergo alterations leading to photoaging, inflammation, immune dysfunction, imbalanced epidermal homeostasis, or other skin disorders. Modern nutritional science is developing new insights into the relation between food intake and health, and effects of food ingredients may prove to be biologically relevant for optimal skin condition. The objective of this review was to evaluate the present knowledge about the interrelation of nutrients and skin, particularly the photoprotective effects of nutrients, the influences of nutrients on cutaneous immune responses, and therapeutic actions of nutrients in skin disorders. The nutrients of focus were vitamins, carotenoids, and polyunsaturated fatty acids. Supplementation with these nutrients was shown to provide protection against ultraviolet light, although the sun-protection factor was relatively small compared with that of topical sunscreens. An increase in delayed-type hypersensitivity skin responses after supplementation with nutrients has proven beneficial, especially in elderly people, and may boost cell-mediated immunity. Dietary consumption of certain plants or fish oil is known to modulate the balance of lipid inflammatory mediators and, therefore, is valuable in the treatment of inflammatory skin disorders. It was concluded that nutritional factors exert promising actions on the skin, but information on the effects of low-to-moderate doses of nutrients consumed long term by healthy individuals is obviously lacking, as are data on direct effects on basal skin properties, including hydration, sebum production, and elasticity.

Essential fatty acid metabolism and its modification in atopic eczema

Research from the 1930s to the 1950s established that a deficit of n-6 essential fatty acids (EFAs) leads to an inflammatory skin condition in both animals and humans. In a common inherited skin condition, atopic dermatitis (eczema), there was evidence of low blood EFA concentrations and of a therapeutic response to exceptionally high doses of linoleic acid. More recently, it has been established that there is no deficit of linoleic acid in atopic eczema. Concentrations of linoleic acid instead tend to be elevated in blood, milk, and adipose tissue of patients with atopic eczema, whereas concentrations of linoleic acid metabolites are substantially reduced. This suggests reduced conversion of linoleic acid to gamma-linolenic acid (GLA). In most but not all studies, administration of GLA has been found to improve the clinically assessed skin condition, the objectively assessed skin roughness, and the elevated blood catecholamine concentrations of patients with atopic eczema. Atopic eczema may be a minor inherited abnormality of EFA metabolism.