The role of fish oil in psoriasis. A randomized, double-blind, placebo-controlled study to evaluate the effect of fish oil and topical corticosteroid therapy in psoriasis

Dietary Intervention and Supplements in the Management of Psoriasis: Current Perspectives

Nutrition is a complex topic encompassing diet and a variety of supplements including vitamins, fish oil, herbal products, and probiotics. Patients with psoriasis display high interest in understanding the potential impact of nutritional modifications on their psoriasis. In this review, we examine the evidence for nutritional interventions in psoriasis and summarize important concepts. We found that certain diets, such as low-calorie diets for obese patients, gluten-free diets for patients with comorbid celiac disease, and the Mediterranean diet, may have benefits for psoriasis patients. Supplements in general do not show strong evidence of benefit, though more studies are required given the heterogeneity of these trials. Finally, the gut microbiome has drawn considerable interest in recent years, with specific probiotics showing promising results for psoriasis patients and warranting further exploration.

Free Fatty Acid Receptor 4 (FFA4) Activation Ameliorates Imiquimod-Induced Psoriasis in Mice

Dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) has been used as an adjunct therapy for psoriasis due to its anti-inflammatory properties. Free fatty acid receptor 4 (FFA4 or GPR120) is a receptor-sensing n-3 PUFA. In the present study, we examined whether FFA4 acted as a therapeutic target for n-3 PUFA in psoriasis therapy. Experimentally, psoriasis-like skin lesions were induced by treatment with imiquimod for 6 consecutive days. A selective FFA4 agonist, Compound A (30 mg/kg), was used in FFA4 WT and FFA4 KO mice. Imiquimod-induced psoriasis-like skin lesions, which present as erythematous papules and plaques with silver scaling, as well as markedly elevated IL-17/IL-23 cytokine levels in skin tissues, were significantly suppressed by Compound A in FFA4 WT mice, but not in FFA4 KO mice. Enlarged lymph nodes and spleens, as well as imiquimod-induced, elevated IL-17/IL-23 cytokine levels, were also strongly suppressed by Compound A in FFA4 WT mice, but not in FFA4 KO mice. Imiquimod-induced increases in the CD4⁺IL-17A⁺ T cell population in lymph nodes and spleens were suppressed by Compound A treatment in FFA4 WT mice; however, this was not seen in FFA4 KO mice. Furthermore, compound A suppressed the differentiation of CD4⁺ naïve T cells from splenocytes into T_H17 cells in an FFA4-dependent manner. In conclusion, we demonstrated that the activation of FFA4 ameliorates imiquimod-induced psoriasis, and the suppression of the differentiation of T_H17 cells may partly contribute to its efficacy. Therefore, we suggest that FFA4 could be a therapeutic target for psoriasis therapy.

The Effect of Antioxidant and Anti-Inflammatory Capacity of Diet on Psoriasis and Psoriatic Arthritis Phenotype: Nutrition as Therapeutic Tool?

Chronic inflammation and increased oxidative stress are contributing factors to many non-communicable diseases. A growing body of evidence indicates that dietary nutrients can activate the immune system and may lead to the overproduction of pro-inflammatory cytokines. Fatty acids as macronutrients are key players for immunomodulation, with n-3 polyunsaturated fatty acids having the most beneficial effect, while polyphenols and carotenoids seem to be the most promising antioxidants. Psoriasis is a chronic, immune-mediated inflammatory disease with multifactorial etiology. Obesity is a major risk factor for psoriasis, which leads to worse clinical outcomes. Weight loss interventions and, generally, dietary regimens such as gluten-free and Mediterranean diet or supplement use may potentially improve psoriasis’ natural course and response to therapy. However, data about more sophisticated nutritional patterns, such as ketogenic, very low-carb or specific macro- and micro-nutrient substitution, are scarce. This review aims to present the effect of strictly structured dietary nutrients, that are known to affect glucose/lipid metabolism and insulin responses, on chronic inflammation and immunity, and to discuss the utility of nutritional regimens as possible therapeutic tools for psoriasis and psoriatic arthritis.

Joint AAD-NPF Guidelines of care for the management and treatment of psoriasis with topical therapy and alternative medicine modalities for psoriasis severity measures

Psoriasis is a chronic, inflammatory, multisystem disease that affects up to 3.2% of the United States population. This guideline addresses important clinical questions that arise in psoriasis management and care and provides recommendations based on the available evidence. The treatment of psoriasis with topical agents and with alternative medicine will be reviewed, emphasizing treatment recommendations and the role of dermatologists in monitoring and educating patients regarding benefits as well as risks that may be associated. This guideline will also address the severity assessment methods of psoriasis in adults.

Efficacy of fish oil and its components in the management of psoriasis: a systematic review of 18 randomized controlled trials

Context

Fish oil and omega-3 polyunsaturated fatty acids (ω-3 PUFAs) have anti-inflammatory properties, but their effect on psoriasis and its comorbidities remains inconclusive.

Objective

The aim of this quantitative systematic review was to evaluate the efficacy and safety of fish oil and its components in the treatment of psoriasis and its comorbidities.

Data Sources

PubMed, Embase, Cochrane Central Register of Controlled Trials, China Network Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang databases were searched from inception to March 30, 2019.

Study Selection

Randomized controlled trials were eligible for inclusion if they measured the effect of fish oil and its components in the treatment of patients with psoriasis.

Data Extraction

Eighteen randomized controlled trials involving 927 study participants were included.

Results

Monotherapy with fish oil or ω-3 PUFAs had no effect on the Psoriasis Area and Severity Index (PASI) score (P = 0.47), lesion area (P = 0.34), or pruritus (P = 0.62). Fish oil or ω-3 PUFAs combined with conventional treatments, however, resulted in a decreased PASI score (mean difference [MD], −3.92; 95%CI, −6.15 to −1.69; P = 0.0006) and lesion area (MD, −30.00; 95%CI, −33.82 to −26.18; P < 0.0001). Safety evaluation suggested no between-group differences. Fish oil and its components reduced certain risk factors for obesity, cardiovascular disease, and metabolic disease in patients with psoriasis and also regulated several inflammatory mediators.

Conclusions

Overall, when combined with conventional treatments, fish oil and its components may have beneficial effects on psoriasis and its comorbidities, including obesity, cardiovascular disease, and metabolic disease.

Systematic Review Registration

PROSPERO registration number CRD42019128631.

Omega-3 Versus Omega-6 Polyunsaturated Fatty Acids in the Prevention and Treatment of Inflammatory Skin Diseases

Omega-3 (ω-3) and omega-6 (ω-6) polyunsaturated fatty acids (PUFAs) are nowadays desirable components of oils with special dietary and functional properties. Their therapeutic and health-promoting effects have already been established in various chronic inflammatory and autoimmune diseases through various mechanisms, including modifications in cell membrane lipid composition, gene expression, cellular metabolism, and signal transduction. The application of ω-3 and ω-6 PUFAs in most common skin diseases has been examined in numerous studies, but their results and conclusions were mostly opposing and inconclusive. It seems that combined ω-6, gamma-linolenic acid (GLA), and ω-3 long-chain PUFAs supplementation exhibits the highest potential in diminishing inflammatory processes, which could be beneficial for the management of inflammatory skin diseases, such as atopic dermatitis, psoriasis, and acne. Due to significant population and individually-based genetic variations that impact PUFAs metabolism and associated metabolites, gene expression, and subsequent inflammatory responses, at this point, we could not recommend strict dietary and supplementation strategies for disease prevention and treatment that will be appropriate for all. Well-balanced nutrition and additional anti-inflammatory PUFA-based supplementation should be encouraged in a targeted manner for individuals in need to provide better management of skin diseases but, most importantly, to maintain and improve overall skin health.

Effects of fish oil supplement on psoriasis: a meta-analysis of randomized controlled trials

BACKGROUND

Fish oils, which contain omega-3 polyunsaturated fatty acids as the active ingredients, possess anti-inflammatory activities and may have therapeutic potential in diseases with an inflammatory etiology. Fish oil supplement has been advocated for treating psoriasis which is a chronic inflammatory dermatosis.

OBJECTIVE

We aimed to investigate the effects of fish oil supplement on psoriasis.

METHODS

We searched CENTRAL, Embase and MEDLINE on 24 January 2018 for randomized control trials (RCTs) on the effects of fish oil supplement in treating psoriasis. The Cochrane Collaboration's tool was used to assess the risk of bias of included RCTs. We performed a random-effects model meta-analysis to obtain the pooled treatment effect estimates.

RESULTS

We included 13 RCTs with 625 participants. Three RCTs involving 337 participants provided usable data for meta-analysis. Fish oil supplement did not significantly reduce the severity of psoriasis when assessed by Psoriasis Area and Severity Index score (mean difference - 0.28; 95% confidence interval - 1.74 to 1.19).

CONCLUSION

The current evidence does not support the use of fish oil supplement in treating psoriasis.

Effect of omega-3 fatty acids on disease severity in patients with psoriasis: A systematic review

AIM

Many randomized controlled trials have been performed on the efficacy and mechanism of action of omega-3 polyunsaturated fatty acids (n-3 PUFAs) on psoriasis. However, contradictory results have been obtained. This study wants to assess the effects of n-3 PUFAs on the severity of psoriasis.

METHODS

The Cochrane Central Register of Controlled Trials, PubMed/MEDLINE and EMBASE were searched for all randomized controlled trials and prospective observational studies comparing the efficacy of n-3 PUFAs versus control in adult patients with psoriasis. The primary outcome was psoriasis severity as measured by the Psoriasis Area Severity Index (PASI) score.

RESULTS

The initial search yielded 732 articles, 720 of which were excluded. The data of the 12 remaining studies were extracted. Some studies found that n-3 PUFAs were associated with improvements in the PASI score, erythema, scaling, itching, area involved and infiltration. However, some studies did not find reduction in scaling, erythema, area involved or thickness in the treatment group.

CONCLUSION

It is still inconclusive whether use of n-3 PUFAs in patients with psoriasis is associated with improvements in severity of psoriasis and other outcomes.

XP-828L in the Treatment of Mild to Moderate Psoriasis: Randomized, Double-Blind, Placebo-Controlled Study

Background:

XP-828L, a protein extract obtained from sweet whey, has demonstrated potential benefit for the treatment of mild to moderate psoriasis in an open-label study.

Objective:

To study in a randomized, double-blind, placebo-controlled study the safety and efficacy of XP-828L in the treatment of mild to moderate psoriasis.

Design:

XP-828L 5 g/d (group A, n = 42) or placebo (group B, n = 42) was given orally for 56 days followed by XP-828L 5 g/d in group A and by XP-828L 10 g/d in group B for an additional 56 days.

Results:

Patients receiving XP-828L 5 g/d for 56 days had an improved Physician's Global Assessment (PGA) score compared with patients under placebo ( p < .05). Considering the data of group A only, the PGA score improved from day 1 to day 56 ( p < .01); the Psoriasis Area and Severity Index score improved as well, but to a lesser extent ( p < .05).

Conclusion:

Oral administration of 5 g/d XP-828L compared with a placebo significantly improved the PGA score of patients with mild to moderate psoriasis.

Diet in dermatology: Part II. Melanoma, chronic urticaria, and psoriasis

The roles of dietary factors in aggravating, preventing, or treating skin diseases are common questions encountered in dermatology practice. Part II of this two-part series reviews dietary modifications that can potentially be utilized in the management of melanoma, chronic urticaria, and psoriasis patients. Specifically, we examine the effect of alcohol consumption and supplementation with vitamins D and E, polyunsaturated fatty acids, selenium, green tea, resveratrol, and lycopene on melanoma risk. The relationships between chronic urticaria symptoms and dietary pseudoallergens, gluten, and vitamin D are analyzed. We explore weight loss, reduced alcohol consumption, and gluten avoidance as means of reducing psoriasis-associated morbidity, as well as the possible utility of supplementation with polyunsaturated fatty acids, folic acid, vitamin D, and antioxidants. With proper knowledge of the role of diet in these cutaneous disease processes, dermatologists can better answer patient inquiries and consider implementation of dietary modifications as adjuncts to other treatments and preventative measures.

Oral herbal medicines for psoriasis: a review of clinical studies

Various forms of complementary and alternative medicine are used in psoriasis. Among these, herbal medicines are frequently used as systemic and/or topical interventions either as a replacement for or in conjunction with conventional methods. The benefit of such use is unclear. This review is to provide an up-to-date review and discussion of the clinical evidence for the main kinds of herbal therapies for psoriasis. Searches of the biomedical databases PubMed (including MEDLINE), EMBASE and CINAHL were conducted in December 2011 which identified 32 clinical studies, all published in English. Twenty of these primarily tested topical herbal medicines and were thus excluded. The 12 studies that evaluated systemic use of herbal medicines were included in the review. Four were case series studies and the other 8 were controlled trials. In terms of interventions, 4 studies tested the systemic use of plant oils combined with marine oils and 8 studies tested multi-ingredient herbal formulations. The clinical evidence for plant and animal derived fatty acids is inconclusive and any benefit appears to be small. For the multi-herb formulations, benefits of oral herbal medicines were shown in several studies, however, a number of these studies are not controlled trials, a diversity of interventions are tested and there are methodological issues in the controlled studies. In conclusion, there is promising evidence in a number of the studies of multi-herb formulations. However, well-designed, adequately powered studies with proper control interventions are needed to further determine the benefits of these formulations. In addition, syndrome differentiation should be incorporated into trial design to ensure effective translation of findings from these studies into Chinese medicine clinical practice.

Complementary and alternative medicine for psoriasis: a qualitative review of the clinical trial literature

BACKGROUND

Patients with psoriasis often inquire about complementary and alternative medicine in an effort to do everything possible to control the disease.

OBJECTIVE

We sought to review the clinical trial literature regarding complementary and alternative medicine for the treatment of psoriasis.

METHODS

We conducted qualitative systematic review of randomized, clinical trials.

RESULTS

Although many randomized controlled trials were found, both the results and the quality of the studies varied.

LIMITATIONS

The main limitations were the relatively low quality of studies (as assessed by Jadad scores), lack of inclusion of unpublished studies, and the fact that only one author determined inclusion of studies and assignment of Jadad scores.

CONCLUSION

There is a large body of literature in regard to complementary and alternative medicine for the treatment of psoriasis. More work is necessary before these modalities should be recommended to our patients.

XP-828L (Dermylex), a new whey protein extract with potential benefit for mild to moderate psoriasisThis article is one of a selection of papers published in this special issue (part 1 of 2) on the Safety and Efficacy of Natural Health Products

Natural health products (NHPs) or complementary and alternative medicine (CAM) are commonly used to prevent disorders or support the usual treatments of many diseases. XP-828L, a whey protein extract, has demonstrated potential benefits for the treatment of mild to moderate psoriasis. The aim of this study was to analyze further clinical data that demonstrated the clinical benefits and safety of the XP-828L in patients with psoriasis and the potential mechanism of action of this product in vitro. Oral administration (2.5 g, twice a day, over 112 days) of XP-828L in 42 human subjects with mild to moderate psoriasis improved their PGA scores (physician’s global assessment). Moreover, no significant changes in haematology or hepatic and renal parameters were observed throughout the study period, indicating the safety of the product. In vitro experiments showed that XP-828L decreased the proliferation of concanavalin A (ConA)-stimulated murine splenocytes and their production of interleukin (IL)-2 and interferon (IFN)-γ. Although the in vivo mechanism of action of XP-828L remains unknown, XP-828L represents an NHP to be used as an alternative or concomitant treatment for mild to moderate psoriasis and potentially for other immune-mediated diseases.

[The significance of diet and associated factors in psoriasis]

Psoriasis is a T cell mediated inflammatory skin disease characterized by hyperproliferation and reduced differentiation of epidermal keratinocytes. In severe cases, the disease can result in an insufficient nutritional status which may even be promoted by nutrient-drug interactions. Both the general diet and single food components have been suggested to play a role in etiology and pathogenesis of psoriasis. Fasting periods, vegetarian diets, and diets rich in omega-3 polyunsaturated fatty acids from fish oil have all been associated with improvement in some studies. The most likely explanation is the reduced amounts of arachidonic acid and the increased eicosapentaenoic acid intake resulting in a modulated eicosanoid profile. However, only one of four controlled studies showed a benefit of omega-3 fatty acids compared to placebo. Some psoriasis patients are gluten-sensitive and may benefit from a gluten free diet. The active form of vitamin D exhibits anti-proliferative and immunoregulatory effects and has been shown to be useful in the treatment of psoriasis.

Diet and psoriasis: experimental data and clinical evidence

Psoriasis is considered as a T-cell-mediated inflammatory skin disease which is characterized by hyperproliferation and poor differentiation of epidermal keratinocytes. While susceptibility to psoriasis is inherited, the disease is influenced by environmental factors such as infections and stress. Diet has been suggested to play a role in the aetiology and pathogenesis of psoriasis. Fasting periods, low-energy diets and vegetarian diets improved psoriasis symptoms in some studies, and diets rich in n-3 polyunsaturated fatty acids from fish oil also showed beneficial effects. All these diets modify the polyunsaturated fatty acid metabolism and influence the eicosanoid profile, so that inflammatory processes are suppressed. Some patients with psoriasis show an elevated sensitivity to gluten. In patients with IgA and/or IgG antigliadin antibodies the symptoms have been shown to improve on a gluten-free diet. The active form of vitamin D, 1,25-dihydroxyvitamin D(3), exhibits antiproliferative and immunoregulatory effects via the vitamin D receptor, and thus is successfully used in the topical treatment of psoriasis. In this review, dietary factors which play a role in psoriasis are assessed and their potential benefit is evaluated. Furthermore, the risk of drug-nutrient interactions in psoriasis therapy is discussed.

The clinical benefit of moisturizers

Moisturizing creams marketed to consumers often contain trendy ingredients and are accompanied by exciting names and attractive claims. Moisturizers are also an important part of the dermatologist's armamentarium to treat dry skin conditions and maintain healthy skin. The products can be regarded as cosmetics, but may also be regulated as medicinal products if they are marketed against dry skin diseases, such as atopic dermatitis and ichthyosis. When moisturizers are used on the so-called dry skin, many distinct disorders that manifest themselves with the generally recognized symptoms of dryness are treated. Dryness is not a single entity, but is characterized by differences in chemistry and morphology in the epidermis depending on the internal and external stressors of the skin. Patients and the society expect dermatologists and pharmacists to be able to recommend treatment for various dry skin conditions upon evidence-based medicine.

LEARNING OBJECTIVE

Upon completing this paper, the reader should be aware of different types of moisturizers and their major constituents. Furthermore, s/he will know more about the relief of dryness symptoms and the functional changes of the skin induced by moisturizers.

Effectiveness of kukui nut oil as a topical treatment for psoriasis

BACKGROUND

No cure for psoriasis exists for the 1-3% of the American population who suffer from it; however, anecdotal reports from patients with psoriasis visiting Hawaii who purchased kukui nut oil, claim it helped reduce the severity of their lesions.

OBJECTIVE

This pilot study was a double-blind, placebo-controlled clinical trial to determine the effectiveness of kukui nut oil as a topical treatment for psoriasis.

METHODS

Thirty adult subjects (18-78 year) were recruited from the community for a 12-week randomized, double-blind, placebo-controlled pilot study. Subjects were previously diagnosed with mild, stable plaque psoriasis (less than 15% of total body surface area [TBSA]) and agreed to abstain from other treatments during the course of the study. Following a 4-week washout period the subjects were randomized into a treatment group (15 subjects applying kukui nut oil) or a control group (15 applying the mineral oil placebo). Patients were seen every 2 weeks (seven visits at 0, 2, 4, 6, 8, 10, and 12 weeks) by a dermatological nurse practitioner under the general supervision of a board certified dermatologist. Measurable outcomes included evaluation of one targeted lesion and of the overall severity of their psoriasis using clinical evaluation, Psoriasis Area and Sensitivity Index (PASI), Global Severity of Psoriasis Scale, and photographs. Each patient also evaluated their own lesions daily using the Global Severity of Psoriasis Scale, and noted any side-effects or other treatments used.

RESULTS

Although both groups improved, we found no significant difference between the treatment (kukui nut oil) and the placebo (mineral oil) among the 24 out of 30 subjects (80%) who completed the study. No side-effects or adverse events were reported.

CONCLUSION

Kukui nut oil did not significantly reduce symptoms of psoriasis; however, this was a small pilot study, and the use of this oil cannot be dismissed without using a larger study population of patients with psoriasis.

Role of topical emollients and moisturizers in the treatment of dry skin barrier disorders

Emollients and moisturizing creams are used to break the dry skin cycle and to maintain the smoothness of the skin. The term 'moisturizer' is often used synonymously with emollient, but moisturizers often contain humectants in order to hydrate the stratum corneum. Dryness is frequently linked to an impaired barrier function observed, for example, in atopic skin, psoriasis, ichthyosis, and contact dermatitis. Dryness and skin barrier disorders are not a single entity, but are characterized by differences in chemistry and morphology in the epidermis. Large differences also exist between moisturizing creams. Moisturizers have multiple functions apart from moistening the skin. Similar to other actives, the efficacy is likely to depend on the dosage, where compliance is a great challenge faced in the management of skin diseases. Strong odor from ingredients and greasy compositions may be disagreeable to the patients. Furthermore, low pH and sensory reactions, from lactic acid and urea for example, may reduce patient acceptance. Once applied to the skin, the ingredients can stay on the surface, be absorbed into the skin, be metabolized, or disappear from the surface by evaporation, sloughing off, or by contact with other materials. In addition to substances considered as actives, e.g. fats and humectants, moisturizers contain substances conventionally considered as excipients (e.g. emulsifiers, antioxidants, preservatives). Recent findings indicate that actives and excipients may have more pronounced effects in the skin than previously considered. Some formulations may deteriorate the skin condition, whereas others improve the clinical appearance and skin barrier function. For example, emulsifiers may weaken the barrier. On the other hand, petrolatum has an immediate barrier-repairing effect in delipidized stratum corneum. Moreover, one ceramide-dominant lipid mixture improved atopic dermatitis and decreased transepidermal water loss (TEWL) in an open-label study in children. In double-blind studies moisturizers with urea have been shown to reduce TEWL in atopic and ichthyotic patients. Urea also makes normal and atopic skin less susceptible against irritation to sodium laurilsulfate. Treatments improving the barrier function may reduce the likelihood of further aggravation of the disease. In order to have optimum effect it is conceivable that moisturizers should be tailored with respect to the epidermal abnormality. New biochemical approaches and non-invasive instruments will increase our understanding of skin barrier disorders and facilitate optimum treatments. The chemistry and function of dry skin and moisturizers is a challenging subject for the practicing dermatologist, as well as for the chemist developing these agents in the pharmaceutical/cosmetic industry.

Treatment pearls from Europe

Discussing the need for psychological treatment of a dermatological condition with children and families can be a daunting task. Families must be given accurate information about the role of psychological or behavioral factors in the exacerbation or maintenance of their child's condition; however, this information must be presented in a way that families and children do not feel criticized or judged. This article discusses nondrug treatments of skin diseases.

Diet and dermatology. The role of dietary manipulation in the prevention and treatment of cutaneous disorders

The role of dietary manipulation and vitamins in the prevention and treatment of certain skin diseases is reviewed. Manipulation of nutrition by either diet restriction or supplementation can effect cutaneous disorders such as skin cancer, wound healing, atopic dermatitis, psoriasis, and dermatitis herpetiformis.