# Role of Nutribiotics in Skin Care
## 5 Nutribiotics: An Opportunity to Improve Skin Health
### Atopic Dermatitis
The presence of key microbial drivers, including _Bacteroules fragilis_ and _Lactobacillus acidophilus_, was significantly increased at week 8. The authors also found that high responsiveness to an 8-week probiotic treatment was associated with improvements in the gut microbiome profile with greater relative abundance of probiotic species [157]. Post- and xenobiotics were also studied. In 2016, [PERSON] et al. [215] assessed the effect of heat-killed _Enterococcus faecalis_ EF-2001 (EF-2001) on AD in an in vivo AD model by repeated local exposure of _Dermatophagoides farinae_ extract, finding that the symptoms and pathological signs were attenuated and so was the production of Ig and the expression of various pathogenic cytokines in the ears, lymph nodes, and splenocytes. Considering previous studies in allergic diseases, which reported that heat-killed _Lactobacillus casei_ Shirota suppressed pro-inflammatory, Th1, and Th2 cytokines in splenocytes [216], authors suggested that EF-2001 is able to significantly inhibit the inflammatory response by blocking both Th1 and Th2 in AD lesions of the tissues in the ears as well as in the cervical lymph nodes and splenocytes [215]. Formulas including a mixture of prebiotics, probiotics, and postbiotics have also been tested. Patients with a diagnosis of AD were treated for 8 weeks with an oral formula containing seven types of gastro-resistant probiotics (mixture of _Lactobacillus rhamous_ GG, _Lactobacillus acidophilus_ GKA7, _Lactococcus lactis_ GKL2, _Lactobacillus casei_ GKC1, _Lactobacillus paracasei_ GK56, _Bifidobacterium bifidum_ GKB2, and _Bifidobacterium lactis_ GKK2, no less than \(2\times 10^{10}\) CFU/capsule), a postbiotic heat-killed _Lactobacillus plantarum_ (10 mg/capsule), and triple prebiotics containing inulin (22 mg/capsule), galactooligosaccharides (8.1 mg/capsule), and fructooligosaccharides (0.9 mg/capsule). Results showed an improvement in the diversity of the gut microbiome and a significant improvement in AD severity [182]. [PERSON] et al. [183] performed a real-life, multi-center, retrospective observational investigation designed to evaluate the efficacy and tolerability of a commercial pre- and post-biotic supplement. Patients consumed a daily sachet containing a concentration exceeding \(2.5\times 10^{9}\) AFU (active fluorescent units) of three patented probiotic species: _Bifidobacterium_animals_ subsp. lactis BS01 (LMG P-21384), _Lacticasebiacillus rhamnus_ LR05 (DSM 19739), and _Lactiplantibacillus plantarum_ LP14 (DSM 33401). Results showed a significant overall and even intra-individual reduction in all severity scores: erythema, edema/papules, excoriation, TIS (Three Item Severity score), and PRURISCORE [183]. While the use of orally administered probiotics for the prevention and treatment of AD have been largely studied, only a small number of studies have focused on the topical application of probiotics, which may be due to the difficulty of delivering viable bacteria to the skin, given that creams and lotions typically have to be preserved [217]. The most used probiotics and postbiotics for a topical application in AD are heat-inactivated _Lactobacillus jolnsonii_ NCC5533 [218], _Aquaphilus dolomiae_, and _Vitreoscilla filiformis_, which are able to reduce _S. aureus_ colonization [219], and _Lactobacillus reuteri_ DSM 17938, which showed a statistically and clinically significant improvement in the SCORAD index and local SCORAD in adults suffering from AD after 4 and 8 weeks of continuous use [220]. Previous studies showed that the production of the anti-inflammatory molecule IL-10 by dendritic cells was increased after a local application of _Vitreoscilla filiformis_ extracts on skin with AD [221; 222]. In a study performed by [PERSON] et al. [223], a strain of _Staphylococcus hominis_ A9 (ShA9) was selected and applied to the skin of patients with AD, showing that ShA9 can inhibit skin inflammation by inhibiting quorum sensing. Phase II of clinical trials is ongoing, and results are still not available.