The Regenerative Potential of Donkey and Human Milk on the Redox-Sensitive and Proliferative Signaling Pathways of Skin Fibroblasts

Abstract

The influence of milk bioactive peptides on skin regenerative potential and rejuvenation is very often limited because of allergic reactions. The current study is aimed at exploring the influence of donkey colostrum and mature milk, human colostrum and mature milk, and β-casein and β-casomorphine-7, on the growth and inflammatory response of the culture of cultured skin fibroblasts exposed to these conditions for twenty-four hours. Their effects on the growth-regulatory kinases and redox-sensitive, proinflammatory transcriptional factor NF-κB were detected by using specific primary antibodies against NF-κB p65, Akt-1, phospho-Akt-1, Erk-1, phospho-Erk-1, JNK, phospho-JNK, phospho-STAT-1, and CD26, while logarithmic integrated fluorescence intensity patterns were recorded by flow cytometry. The downregulation of NF-κB p65 was observed after the exposure of skin fibroblasts to donkey milk and human colostrum, while β-casein and β-casomorphine-7 exerted the opposite effect, which suggests that noncasein bioactive peptides of donkey and human milk may be responsible for anti-inflammatory properties. The exposure to all milk species examined and β-casein leads to the activation of growth-regulatory kinases (Akt1/2/3 kinase, Erk kinase, JNK kinase, and Stat-1 kinase), especially for the p-Erk pathway, which suggests that essential amino acids of casein may be responsible for Erk-induced cell cycle activation and proliferation. The opposite effect was observed when cells were exposed to β-casomorphine-7, which may affect the skin fibroblast survival and their proliferative and regenerative potential. Donkey milk did not significantly change the CD26 antigen expression. In conclusion, our results suggest that among cell signaling molecules, the most sensitive but nonspecific downstream effector is p-Erk kinase, which may point to donkey milk usefulness in wound healing, regenerative, and aesthetic dermatology. The noncasein bioactive peptides of donkey milk may be responsible for the anti-inflammatory property of donkey milk and colostrum, which may indicate the usefulness in the treatment of inflammatory skin diseases.

Milk Proteins—Their Biological Activities and Use in Cosmetics and Dermatology

“…Accordingly, it can be concluded that casein amino acids may be responsible for the activation and proliferation of the cell cycle initiated by Erk. It suggests that noncasein bioactive peptides of donkey and human milk may be responsible for anti-inflammatory properties and may be useful in wound healing, regenerative, and aesthetic dermatology [ 185 ].…”

The Potential of Bovine Colostrum-Derived Exosomes to Repair Aged and Damaged Skin Cells

“…The expression level of type 1 collagen was significantly increased with milk exosomes, especially Col M-exo in UV radiation-exposed fibroblasts. According to the previous studies, bovine milk induces type 1 collagen synthesis through the STAT6 pathway in human fibroblast [48] and donkey and human milk activate growth-regulatory kinases, especially the p-ERK pathway, promoting cell cycle and proliferation of skin fibroblasts in vitro [27]. Additionally, we conducted a wound-scratch test to confirm the migration promoting effect of Col M-exo.…”

“…Taken together, these findings suggest that Col M-exo can effectively promote ECM construction by improving survival of skin fibroblasts and collagen production under UV irradiation, offering strength and elasticity to the skin. broblasts in vitro [27]. Additionally, we conducted a wound-scratch test to confirm the migration promoting effect of Col M-exo.…”

“…This solution is absorbed through the gastrointestinal tract (GI) and is involved in the growth, development, nutrition, and differentiation of primary keratinocytes in newborns [23,24]. Recent studies have found that bovine milk is able to promote healing of full thickness wounds with increased fibroblasts and collagen fibers [25][26][27]. In particular, colostrum is typically more enriched in immune and bioactive factors than mature milk made during lactation.…”

Mesenchymal stem cell‐derived exosomes and skin photoaging: From basic research to practical application

“…75 collagen synthesis through the STAT6 pathway in human fibroblast 91 and donkey and human milk exosomes activate the p-ERK pathway, promoting cell cycle and proliferation of skin fibroblasts in vitro. 92 Human trophoblast exosomes (hTB-Exos) stimulated a decrease in MMP gene expression and an increase in collagen, elastin, and fibronectin gene expression in human normal dermal fibroblasts (HNDFs). The increased expression of genes was associated with C-X-C motif ligand (CXCL) chemokines, toll-like receptors, and nuclear factor-kappa B (NF-κB) signaling.…”