# Role of Nutribiotics in Skin Care
## 4 Skin Microbiome and Dermatological Disorders
\begin{table}
\begin{tabular}{c c c} \hline
**Skin Disease or Condition** & **Microbiome Disbalance** & **Reference** \\ \hline \multirow{8}{*}{Acne} & Proliferation or presence of certain strains of & [PERSON] et al., 2022 [82]; [PERSON] et al., 2017 [84]; _Ctiubacterium acnes_ & 2020 [85]; [PERSON] et al., 2022 [86] \\ \cline{2-3}  & The relative abundance of _S. epidermidis_ & \multirow{2}{*}{[PERSON] et al., 2019 [75]} \\  & increases at the expense of _C. acnes_ & & \\ \cline{2-3}  & _C. acnes_ inhibits the development of & & [2022 [87]; [PERSON] et al., 2019 [88] \\ [PERSON]cline{2-3}  & _Firmicutes_ spp., _Proteobacteria_ spp., _Actinobacteria_ spp., _Stphylococcus_ spp., and & \\ \cline{2-3}  & _Striptococcus_ spp. are increased; _S. epidermidis_ & \\ \cline{2-3}  & _Stphylococcus aureus_ skin colonization & & [2017 [90] \\ \hline \multirow{3}{*}{Atopic Dermatitis} & Increase in the abundance of _S. aureus_ and loss & \multirow{3}{*}{[PERSON] et al., 2019 [91]} \\  & in anaerobic species & & \\ \cline{1-1} \cline{2-3}  & Increase in _Streptococcus_ and _Staphylococcus_ & & [2019 [92] \\ \cline{1-1}  & and decrease in _Malassecia_ and _Ctiubacterium_ & & [2013 [93] \\ \cline{1-1} \cline{2-3}  & Taxonomic diversity reduction; increase in & & [2018 [94] \\ \cline{1-1} \cline{2-3}  & _Firmicutes_ and _Actinobacteria_ & & [2018 [94] \\ \cline{1-1} \cline{2-3}  & Decrease in _Staphylococcus epidermidis_ and & & \\ \cline{1-1} \cline{2-3}  & _Ctiubacterium acnes_ & & [2018 [95] \\ \cline{1-1} \cline{2-3}  & that leads to a higher colonization with & & \\ \cline{1-1} \cline{2-3}  & _Staphylococcus aureus_ & & \\ \hline \end{tabular}
\end{table} 
Table 1: Changes in the skin microbiota profile is the most frequent skin disorders. Acne is a chronic inflammatory skin disease characterized by the presence of comedones, papules, pustules, and sometimes nodules and scars that appear in oily areas of the face and upper trunk. The pathogenesis of acne vulgaris is multifactorial and involves an increased production of cutaneous sebum, hyperplasia of sebaceous glands due to the androgen influence, and infra-infundibulum hyper-keratinization, which leads to ductal obstruction; proliferation, or presence of certain strains of _Cutibacterium acnes_ and the infiltration of inflammatory cells. In terms of skin microbiota changes, _C. acnes_ is considered the most likely acne pathogen, but there are several recognized sub-groups of _C. acnes_ (I, II, and III) and different ribotypes [82]. Thus, more investigations are needed to clarify its role in the pathogenesis of acne. In addition to its role in inflammation, _C. acnes_ also intervenes in the homeostasis of the skin microbiome by interacting with other skin microorganisms, such as _Staphylococcus epidermidis_, _Streptococcus pyogenes_, and _Pseudomonas_ species. In the microbiome of healthy skin, _S. epidermidis_ may limit the over-colomization with _C. acnes_ strains and reduce _C. acnes_-induced II-6 and TNF-c production by keratinocytes. In turn, _C. acnes_ may limit the proliferation of _S. aureus_ and _S. pyogenes_ by promoting triglyceride hydrolysis and propionic acid secretion, which collaborates in the maintenance of the acidic pH in the pilosebaceous follicle. Furthermore, in the pilosebaceous follicles, _C. acnes_ inhibits the development of _S. epidermidis_ by the same mechanisms, hydrolyzing sebum triglycerides, secreting propionic acid, and maintaining the acidic pH of the pilosebaceous follicle [87, 88]. In acne, a modified profile of _C. acnes_ is observed, with different phylotypes differing between patients with and without acne [84, 85, 86]. [PERSON] and [PERSON] [89] carried out a comprehensive review in which studies on the relationships between the skin microbiome and acne vulgaris, rosacea, and skin aging were included. Authors summarized that in acne _Firmicutes_ spp., _Proteobacteria_ spp., _Actinobacteria_ spp., _Staphylococcus_ spp., and _Streptococcus_ spp. were increased, while _S. epidermidis_ were decreased [89].