Prospective Randomized Double-Blind Vehicle-Controlled Study of Topical Coconut and Sunflower Seed Oil-Derived Isosorbide Diesters on Atopic Dermatitis.

Background: Preliminary studies support the use of topical coconut and sunflower seed oil for atopic dermatitis (AD). However, standardized topical formulations of fatty acids from these sources have not been studied. Objective: This study investigates whether coconut oil- and sunflower seed oil-derived isosorbide diesters can be used in conjunction with colloidal oatmeal to improve itch, AD severity, and the need for topical steroids in adults. Methods: This was a single-center, 4-week, randomized, double-blind, and vehicle-controlled study conducted between 2021 and 2022. Thirty-two male and female adults with mild-to-moderate AD were enrolled and completed the study. Participants were randomized to receive either 0.1% colloidal oatmeal (vehicle) or isosorbide diesters (IDEAS, 4% isosorbide dicaprylate and 4% isosorbide disunflowerseedate) along with 0.1% colloidal oatmeal. The main outcomes of the study were changes in the visual analogue rating of itch and 75% improvement in the Eczema Area and Severity Index score (EASI 75) at 4 weeks. Other measures included the use of topical steroids and the relative abundance of skin Staphylococcus aureus. Results: Participants in the IDEAS group had a 65.6% improvement in itch compared with 43.8% in the vehicle group (P = 0.013). In total, 56.5% and 25% of the those in the IDEAS and vehicle groups, respectively, achieved EASI 75 at 4 weeks (P = 0.07). There was no difference in skin hydration or transepidermal water loss. The relative abundance of S. aureus was decreased in the IDEAS group at week 4 compared with no change in the vehicle group (P = 0.044). Topical corticosteroid use increased in the vehicle group compared with a decrease in the IDEAS group at week 1 (292.5% vs 24.8%; P value = 0.039) and week 2 (220% vs 46%; P value = 0.08). Conclusions: Topical application of emollients containing coconut oil- and sunflower seed oil-derived fatty esters may improve itch, reduce topical steroid use, and reduce the relative abundance of S. aureus in mild-to-moderate AD. CTR number: NCT04831892.

Prospective Randomized, Double-Blind, Placebo-Controlled Study of a Standardized Oral Pomegranate Extract on the Gut Microbiome and Short-Chain Fatty Acids.

Punica granatum L., commonly known as the pomegranate, is an abundant source of polyphenols, including hydrolyzable ellagitannins, ellagic acid, anthocyanins, and other bioactive phytochemicals shown to be effective in defending against oxidative stress, and has immunomodulatory activities. Ellagitannins, and their hydrolyzed product ellagic acid, interact with the gut microbiota to yield secondary metabolites known as urolithins that may have health benefits. The objective of this study was to determine the effects of supplementation with a standardized punicalagin-enriched pomegranate extract, Pomella® (250 mg), on the gut microbiome, circulating short-chain fatty acids, and gut microbial-derived ellagitannin metabolite urolithins. A randomized, double-blind, placebo-controlled study was conducted over 4 weeks on healthy volunteers aged 25-55 years. Subjects were randomly assigned to receive either an oral supplement containing 75 mg of punicalagin or an oral placebo. Stool sample collection and venipuncture were performed to analyze the gut microbiome, SCFAs, and urolithin. There was no significant change in the gut microbial diversity in both cohorts after 4 weeks of intervention, but there was a significantly increased relative abundance of Coprococcus eutectus, Roseburia faecis, Roseburia inullnivorans, Ruminococcus bicirculans, Ruminococcus calidus, and Faecalibacterium prausnitzii. Pomegranate extract (PE) supplementation led to the augmentation of circulating propionate levels (p = 0.02) and an increasing trend for acetate levels (p = 0.12). The pomegranate extract (PE) supplementation group had an increased level of circulating urolithins compared to the placebo group (6.6% vs. 1.1%, p = 0.13). PE supplementation correlated with shifts in the gut microbiome and with higher circulating levels of propionate and acetate. Further studies should explore the implications in larger cohorts and over a longer duration.