## 4 Grape Pomace Extracts and Their Bioactives as Ingredients in Sun Oils for Skin Care
### Impact of Phenolics on the Skin
#### 4.4.4 Cyanidin-3-glucoside  
The most prevalent anthocyanin in nature, cyanidin-3-glucoside, provides photoprotection against UVA and UVB radiation for human keratinocytes; pre-treating the cells with cyanidin-3-glucoside reduces some of the negative effects of UVB exposure [41]. For example, cyanidin-3-glucose exhibited protective effects in human keratinocytes against UVB-induced oxidative stress and apoptosis [42]. More specifically, in a non-tumorigenic human immortalized keratinocyte cell line (HaCaT), cyanidin-3-glucoside decreased the levels of intracellular ROS generated by UVB treatment, as well as the UVB-augmented levels of DNA damage indicators, while cyanidin-3-glucose protected keratinocytes from UVB-induced injury by overturning the disruption of mitochondrial membrane potential and reversing apoptosis. Moreover, in such UVB-exposed cells, the attenuated expression of antiapoptotic protein B-cell lymphoma 2 (Bcl-2) was restored after treatment with cyanidin-3-glucoside, while the expressions of the proapoptotic proteins Bcl-2-associated X (Bax) and the key apoptosis executer cleaved caspase-3 were increased in UVB-irradiated cells and decreased in UVB/cyanidin-3-glucoside-treated cells (Table 2). \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Component Structure** & **Main Findings/Type of Study** & **Year of Study** & **References** \\ \hline
**Rutin** & **Sun Protection** & 2019, 2020 & [33, 38] \\
**Photostability** & **Antisoland Activity** & & \\
**In vitro** & & & \\ \hline \hline \end{tabular}  
* Reconstructed Human Epiderms (RHE) was used to perform in vitro skin irritation, in accordance with Test Guideline number 439 by Organization for Economic Co-operation and Development (OECD) Guidelines for the Testing of Chemicals
* In a 3D Reconstructed Human Tissue model, extract-containing formulations were topically
* dosed for 42 minutes
* Following a 4-2 hour incubation period, the tissue sample was subjected to a 3-hour MTT
* (4.5-D)trifluor(hazard-2)-2-5.diphenyl fluorizedization bromide. Thiazolyl blue tetrazolium
* bromiled solution, at a concentration of 1 mg/mL.
* Using a spectrophotometric, the amount of blue comrazan that developed in live cells was quantified at 570 nm
* The assay’s reliability was assessed using SkinflehcTM RHE (1% Triton X-100).  
\begin{tabular}{c c} \hline
**Epigallocatechin-3-gallate** & **Photoging Prevention** \\ \hline \hline \end{tabular}  
* Investigating the function and processes of EGCG in delaying skin photoaging
* Treatment of Human Skin fibroblasts (BSFs) with UVA and EGCG
* Following treatment, alterations in cell shape, telomeres, antioxidant capacity, cell cycle, and associated genes were assessed
* EGCG regulates TGF \(\beta\)-1, 1656/the cell redox system, MMPs, and TIM-1 and delays
* telomere shortening and UVA-induced photoaging of dermal fibroblasts \(-\) the latter makes it a more appealing target for **photogasing prevention** and treatment  
\end{table} 
Table 2: The main findings of some in vitro studies of the impact of phenolics on the skin. \begin{table} \begin{tabular}{c c c c} \hline \hline
**Component Structure** & \multicolumn{3}{c}{**Main Findings/Type of Study**} & **Year of Study** & **References** \\ \hline
**Caffe Acid/Chlorogenic Acid** & & & \\
**Anti-Winkle** & & & \\
**Skin Elasticity** & & & \\
**Moisture** & & & \\
**In vitro** & & & \\ \hline \hline \end{tabular}