Lysates of a Probiotic, Lactobacillus rhamnosus, Can Improve Skin Barrier Function in a Reconstructed Human Epidermis Model

Abstract

The main function of the skin is to protect the body from the external environment. The barrier function of the skin is mainly provided by the stratum corneum, which consists of corneocytes bound with the corneodesmosomes and lamellar lipids. Skin barrier proteins like loricrin and filaggrin also contribute to the skin barrier function. In various skin diseases, skin barrier dysfunction is a common symptom, and skin irritants like detergents or surfactants could also perturb skin barrier function. Many efforts have been made to develop strategies to improve skin barrier function. Here, we investigated whether the microfluidized lysates of Lactobacillus rhamnosus (LR), one of the most widely used probiotic species for various health benefits, may improve the skin barrier function in a reconstructed human epidermis, Keraskin™. Application of LR lysate on Keraskin™ increased the expression of tight junction proteins; claudin 1 and occludin as determined by immunofluorescence analysis, and skin barrier proteins; loricrin and filaggrin as determined by immunohistochemistry and immunofluorescence analysis and qPCR. Also, the cytotoxicity of a skin irritant, sodium lauryl sulfate (SLS), was alleviated by the pretreatment of LR lysate. The skin barrier protective effects of LR lysate could be further demonstrated by the attenuation of SLS-enhanced dye-penetration. LR lysate also attenuated the destruction of desmosomes after SLS treatment. Collectively, we demonstrated that LR lysate has protective effects on the skin barrier, which could expand the utility of probiotics to skin-moisturization ingredients.

Exploring the wound healing, anti-inflammatory, anti-pathogenic and proteomic effects of lactic acid bacteria on keratinocytes

“…Although live LAB, thanks to their active metabolism, have the advantage to produce potent antimicrobials (e.g., bacteriocins, organic acids, hydrogen peroxide) that could prevent adhesion and growth of some skin pathogens, they are generally not preferred in topical application, especially in situations where the skin barrier is breached 8 , 13 . In a wound situation, the potential risks of live LAB entering the bloodstream through breached skin have not been assessed, thus it is usually preferred to exploit the immunostimulating and anti-inflammatory power of lysates by giving up to antibacterial properties of live LAB 12 .…”

“…For example, Lactobacillus rhamnosus GG lysate accelerates re-epithelialization of keratinocyte monolayers by increasing the expression of CXCL2 chemokine and of its receptor, CXCR2, that induce the keratinocyte migration 7 . Very recently, it has been also showed that Lactobacillus rhamnosus LR lysate improves skin barrier function in a reconstructed human epidermis model 8 , and that a multi-strain probiotic formulation, used as a topical treatment, improve the healing of infected chronic ischemic wound lesion 9 . Moreover, Lactobacillus reuteri ATCC-55730 exerts an anti-inflammatory effect on infected keratinocytes by reducing their transcription level of interleukin (IL)-8 and human-beta-defensin (hBD)-2 10 ; while Lactobacillus plantarum K8 inhibits tumor necrosis factor-alpha (TNF-α) or interferon-gamma (IFN-γ) expression in keratinocytes through the lipoteichoic acid that is contained in its cell wall 11 .…”

Soluble Fraction from Lysates of Selected Probiotic Strains Differently Influences Re-Epithelialization of HaCaT Scratched Monolayer Through a Mechanism Involving Nitric Oxide Synthase 2

“…L. bulgaricus, also in this context, did show no effect. IL-6 and IL-8 are reported to be involved in the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway [52]; interestingly Lactobacillus rhamnosus and Lactobacillus reuteri lysates promoted wound healing process via the PI3K/Akt pathway in a reconstructed human epidermis model and gingiva mesenchymal stem cells, respectively [53,54]. Based on these observations, the involvement of the PI3K/Akt pathway in the acceleration of the in vitro wound healing process stimulated by S. thermophilus, L. plantarum, and L. acidophilus samples could be also examined.…”

Ex Vivo Live Full-Thickness Porcine Skin Model as a Versatile In Vitro Testing Method for Skin Barrier Research

“…Rhodamine B, a hydrophilic dye, was applied to evaluate the permeability of the skin as described previously [ 41 ]. Treated tissues were incubated for 24 h and rinsed with PBS.…”