# Role of Nutribiotics in Skin Care
## 5 Nutribiotics: An Opportunity to Improve Skin Health
### Atopic Dermatitis  
There are few studies about the use of oral prebiotics to prevent atopic dermatitis. A meta-analysis by [PERSON] and [PERSON] [196] analyzed 4 studies (1218 infants) exploring the effect of specific prebiotics in the prevention of allergy. They found a significant reduction in eczema when using a fructoligosaccharide and galactooligosaccharide combination [196]. Additionally, another research study showed that infants at risk of atopy who were fed with an oligosaccharideshebiotic-supplemented formula during the first 6 months of life had a significantly lower cumulative incidence of AD in 5 years [149]. Furthermore, a formula containing a specific mixture of neutral oligosaccharides and pectin-derived acidic oligosaccharides was effective as the primary prevention of AD in low-atopy-risk infants [150]. Additionally, [PERSON] et al. [197] demonstrated that AD-like skin lesions induced in NC/Nga mice were reduced via an oral administration of a prebiotic diet (long-chain fructoligosaccharides, inulin, or \(\beta\)-glucan), and intestinal microbiota richness and diversity were also increased with this prebiotic treatment. Several studies confirm the positive effects of oral probiotic supplementation in AD. [PERSON] et al. [198] reviewed the most relevant articles related to the use of probiotics or prebiotics alone and in combination, finding that the most studied probiotics strains were _Lactobacillus_ and _Bifidobacteria_. However, the authors concluded that the results are difficult to interpret as, in many studies, the authors suggest that the disease may tend to improve over time in some groups of patients [198]. Oral supplementation with _Lactobacillus rhamn_ GG (LRGG) for 1 month caused a significant improvement in the AD severity score of the atopic dermatitis (SCORAD) index with decreased levels of inflammatory markers, such as tumor necrosis factor (TNF-\(\alpha\)) and fecal \(\alpha\)1-antitrypsin [151]. LRGG also demonstrated anti-inflammatory activity with significantly increased levels of IL-10 and transforming growth factor-\(\beta\)2 (TGF-\(\beta\)2) in patients with AD [152; 153]. In addition, the administration of probiotic _Lactobacillus_ strains (a mixture of _Lactobacillus rhamnus_ 19070-2 and _Lactobacillus reuteri_ DSM 12246) to children with AD has been shown to result in a moderate improvement in clinical severity [154]. Other studies in vitro and in vivo confirmed the potential use of probiotics in AD. _Lactobacillus casei_ (LC) is one of the most studied species. Several studies in vivo and in vitro showed that LC may exert an immunomododulatory effect, and the active component has been identified as a protein P14 that has been shown to selectively downregulate serum IgE and interleukin-4 cytokine levels as well as the AD index and scratching score in AD-like NC/Nga mice [199]. [PERSON] et al. [200; 201] investigated the immunomododulatory capacity of Duolac ATP, a mixed formulation of probiotics, composed of four different strains of probiotics: _L. casei_ CBT LC5 (KCTC12398 BP), _L. plantarum_ CBT LP3 (KCTC10782 BP), _L. rhamnus_ CBT LR5 (KCTC12202 BP), and _B. lactis_ CBT BL3 (KCTC11904 BP), both in vitro and in vivo [200; 201]. Results showed that Duolac ATP regulated IL-10 and TGF-beta expression and allowed DCs to become functionally tolerant and potentially induce Treg differentiation. Additionally, this formulation regulated transcription factors and cytokines to drive naive T cell differentiation toward Th1 lineages. The authors concluded that this formula could be a good ally in the management of AD symptoms and serve as an immunomododulatory agent for AD [201]. In another study, the probiotic strain _Lactobacillus rhamnus_ GG decreased the proportions of IgA- and IgM-secreting cells in babies with AD. There were no significant differences in the species composition of intestinal bifidobacteria between the studied group and the control group.