The extract used in the study was obtained by extracting dried hydrangeas leaves at 98 ° C for 5 hours in distilled water and then spray drying. The purpose of this study was to study the efficacy of hydrangea leaf hot water extract, which contains a compound called hydrangol. Hydrangea, also known as Tiancha, is used for tea and medicine in Korea, China, and Japan, and researchers in these countries associate it with anti-inflammatory, anti-diabetic, and liver protection activities.
The results of the study published in the journal Nutrition show that in vitro and in vivo experiments show that hydrangea extract can effectively prevent skin photoaging. This extract helps promote collagen deposition and inhibits a group of enzymes called matrix metalloproteinases, which are responsible for the degradation of most extracellular matrix proteins. In addition, through the study of mice, it was found that the production of type I procollagen in the skin tissue of the back of the animal with oral hydrangea extract also potentially indicates the improvement of hydrangea extract on photodamaged skin.
The main findings of the investigators were matrix metalloproteinase expression, production of type I collagenogen, formation of skin wrinkles, and physiological analysis of the skin surface (for hydration and water loss). In the in vitro part of the study, the researchers used fibroblasts from human skin in petri dishes and exposed the samples to ultraviolet B rays. After exposure to sunlight, they added hydrangea extract for 24 hours.
The researchers measured the cell viability and the type of intracellular reactive oxygen species in the sample and found that the regeneration of oxygen was inhibited after treatment of the fibrous tissue with the extract, suggesting an antioxidant effect that may inhibit photoaging damage. It has also been found that although UVB irradiation alters the expression of different enzymes that regulate collagen turnover, Hydrangea extract can reverse the negative patterns associated with collagen degradation.
In vivo experiments in 40 hairless mice, the researchers found the potential effect of hydrangea extract under long-term UV B exposure. In mice supplemented with this extract every day, the skin thickness, wrinkles, and transepidermal water loss of the back skin were reduced, indicating that hydrangea extract may contribute to skin health.