Effects of probiotics supplementation on skin photoaging and skin barrier function: A systematic review and meta-analysis

The influence of lifestyle and environmental factors on host resilience through a homeostatic skin microbiota: An EAACI Task Force Report

Human skin is colonized with skin microbiota that includes commensal bacteria, fungi, arthropods, archaea and viruses. The composition of the microbiota varies at different anatomical locations according to changes in body temperature, pH, humidity/hydration or sebum content. A homeostatic skin microbiota is crucial to maintain epithelial barrier functions, to protect from invading pathogens and to interact with the immune system. Therefore, maintaining homeostasis holds promise to be an achievable goal for microbiome-directed treatment strategies as well as a prophylactic strategy to prevent the development of skin diseases, as dysbiosis or disruption of homeostatic skin microbiota is associated with skin inflammation. A healthy skin microbiome is likely modulated by genetic as well as environmental and lifestyle factors. In this review, we aim to provide a complete overview of the lifestyle and environmental factors that can contribute to maintaining the skin microbiome healthy. Awareness of these factors could be the basis for a prophylactic strategy to prevent the development of skin diseases or to be used as a therapeutic approach.

Limosilactobacillus fermentum MG5368 and Lactiplantibacillus plantarum MG989 Regulates Skin Health in UVB-Induced HaCaT Cells and Hairless Mice Model

BACKGROUND

Photoaging, induced by chronic ultraviolet B (UVB) exposure, results in the degradation of extracellular matrix (ECM) components, leading to skin roughness, wrinkle formation, and reduced elasticity. Recent studies have explored probiotics as potential inhibitors of extrinsic aging, primarily through mechanisms that protect the skin barrier and reduce collagen breakdown.

METHODS

This study investigates the anti-photoaging effects of Limosilactobacillus fermentum MG5368 (L. fermentum MG5368) and Lactiplantibacillus plantarum MG989 (L. plantarum MG989) in UVB-exposed keratinocytes and an SKH-1 hairless mice model.

RESULTS

Both strains demonstrated significant efficacy in preserving collagen through the inhibition of activating protein-1 (AP-1) and reducing the expression of matrix metalloproteinase (MMP)-1 and MMP-3. Additionally, both strains restored COL1A1 protein expressions, thereby enhancing collagen synthesis and ECM stability. Enhanced skin elasticity was observed, attributed to restored levels of hyaluronic acid and hyaluronan synthase 2 (HAS2) protein expressions.

CONCLUSIONS

These findings suggest that L. fermentum MG5368 and L. plantarum MG989 may serve as promising probiotic-based agents for anti-photoaging applications.

Effect of glabridin combined with bakuchiol on UVB-induced skin damage and its underlying mechanism: An experimental study

BACKGROUND

Research has demonstrated the anti-photoaging properties of glabridin and bakuchiol.

METHODS

The impact of glabridin, glabridin + bakuchiol, and bakuchiol on the levels of tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) in mice skin fibroblasts was observed. Furthermore, we investigated the potential roles of fibronectin (FN), interferon-γ (IFN-γ), interleukin-22 (IL-22), and transforming growth factor-β (TGF-β) in the tissues, and evaluated their impact on the enzymatic levels in the skin. In conjunction with transcriptomic analysis, metabolomic profiling, and network pharmacology, all samples underwent comprehensive metabolomic and principal component analysis. The Venny2.1 method was utilized to identify variances in shared metabolites between the treatment group and the UVB group, as well as between the UVB group and the control group. Subsequently, a cluster heat map was generated to forecast and analyze metabolic pathways and targets.

RESULTS

The outcomes from the hematoxylin and eosin and toluidine blue staining revealed that glabridin and bakuchiol markedly decreased dermal thickness and suppressed mast cell infiltration in photoaged mice. Immunohistochemistry and Elisa analysis revealed that glabridin and bakuchiol effectively attenuated the levels of pro-inflammatory factors, including IL-1β, tumor necrosis factor-α, IL-22, and IFN-γ. Furthermore, an increase in the levels of anti-inflammatory factors such as FN and TGF-β was also observed. The determination of the contents of superoxide dismutase, hydroxypropyltransferase and malondialdehyde in mice dorsal skin revealed that glabridin and bakuchiol not only elevated the levels of superoxide dismutase and hydroxyproline, but also reduced malondialdehyde content. Due to the limited number of shared differential metabolites exclusively within Kyoto Encyclopedia of Genes and Genomes, comprehensive pathway enrichment analysis was not feasible.

CONCLUSION

This study demonstrates that glabridin and bakuchiol effectively impede photoaging and alleviate skin inflammation in mice.

A proof of concept: Clinical anti-aging efficacy and safety of Lactiplantibacillus plantarum LB244R® applied topically in a double-blinded placebo-controlled study

BACKGROUND

With the increasing age of the westernized population, there is also increasing economic and aesthetic interest in reducing the signs of skin aging. Additionally, the physical aspect of aging can be displeasing and have detrimental effects psychologically in individuals. Probiotics have shown potential as anti-aging agents, albeit proper studies are needed to confirm their potential.

AIMS

Proving that Lactiplantibacillus plantarum LB244R® could alleviate aging signs relative to its placebo vehicle.

PATIENTS/METHODS

In total, 46 subjects were randomly assigned either the ointment with live bacteria, L. plantarum LB244R® or its vehicle ointment, and had to use the assigned ointment twice daily for 56 days. On Day 0, Day 28, and Day 56 subepidermal low echogenic band (SLEB) thickness, dermal density, skin firmness and elasticity, skin hydration, transepidermal water loss (TEWL), skin pH, collagen fiber visualization using confocal microscopy, Crow's feet, spot score, skin smoothness, and complexion radiance were assessed by dermatologists.

RESULTS

All parameters except TEWL improved relative to their baseline (D0) for the active group. L. plantarum LB244R® improved SLEB thickness, dermal density, skin elasticity, skin hydration, and Crow's feet wrinkle score relative to the placebo vehicle ointment.

CONCLUSION

The study demonstrates an anti-aging effect of L. plantarum LB244R® for topical skin use in the first double-blinded, vehicle-ointment placebo-controlled clinical study.

Transforming Psoriasis Care: Probiotics and Prebiotics as Novel Therapeutic Approaches

Psoriasis is a chronic inflammatory skin disease with autoimmune pathological characteristics. Recent research has found a link between psoriasis, inflammation, and gut microbiota dysbiosis, and that probiotics and prebiotics provide benefits to patients. This 12-week open-label, single-center clinical trial evaluated the efficacy of probiotics (Bacillus indicus (HU36), Bacillus subtilis (HU58), Bacillus coagulans (SC208), Bacillus licheniformis (SL307), and Bacillus clausii (SC109)) and precision prebiotics (fructooligosaccharides, xylooligosaccharides, and galactooligosaccharides) in patients with psoriasis receiving topical therapy, with an emphasis on potential metabolic, immunological, and gut microbiota changes. In total, 63 patients were evaluated, with the first 42 enrolled patients assigned to the intervention group and the next 21 assigned to the control group (2:1 ratio; non-randomized). There were between-group differences in several patient characteristics at baseline, including age, psoriasis severity (the incidence of severe psoriasis was greater in the intervention group than in the control group), the presence of nail psoriasis, and psoriatic arthritis, though it is not clear whether or how these differences may have affected the study findings. Patients with psoriasis receiving anti-psoriatic local therapy and probiotic and prebiotic supplementation performed better in measures of disease activity, including Psoriasis Area and Severity Index, Dermatology Life Quality Index, inflammatory markers, and skin thickness compared with those not receiving supplementation. Furthermore, in the 15/42 patients in the intervention group who received gut microbiota analysis, the gut microbiota changed favorably following 12 weeks of probiotic and prebiotic supplementation, with a shift towards an anti-inflammatory profile.

Effects of Bacterial Lysates and Metabolites on Collagen Homeostasis in TNF-α-Challenged Human Dermal Fibroblasts

During skin aging, the production of extracellular matrix (ECM) proteins, such as type I collagen, decreases and the synthesis of ECM-degrading matrix metalloproteinases (MMPs) rises, leading to an imbalance in homeostasis and to wrinkle formation. In this study, we examined the effects of bacterial lysates and metabolites from three bifidobacteria and five lactobacilli on collagen homeostasis in human dermal fibroblasts during challenge with tumor necrosis factor alpha (TNF-α), modeling an inflammatory condition that damages the skin's structure. Antiaging properties were measured, based on fibroblast cell viability and confluence, amount of type I pro-collagen, ratio of MMP-1 to type I pro-collagen, cytokines, and growth factors. The TNF-α challenge increased the MMP-1/type I pro-collagen ratio and levels of proinflammatory cytokines, as expected. With the probiotics, differences were clearly dependent on bacterial species, strain, and form. In general, the lysates elicited less pronounced responses in the biomarkers. Of all strains, the Bifidobacterium animalis ssp. lactis strains Bl-04 and B420 best maintained type I pro-collagen production and the MMP-1/collagen type I ratio under no-challenge and challenge conditions. Metabolites that were produced by bifidobacteria, but not their lysates, reduced several proinflammatory cytokines (IL-6, IL-8, and TNF-α) during the challenge, whereas those from lactobacilli did not. These results indicate that B. animalis ssp. lactis-produced metabolites, especially those of strains Bl-04 and B420, could support collagen homeostasis in the skin.