Although the sunshine is agreeable, the ultraviolet rays in the sunshine increase the concentration of oxygen free radicals in the skin, destroying collagen and wrinkling the skin. The skin aging caused by light damage is called "photoaging".
According to a study published in the "Molecular Medicine Reports" by the Xiangya Third Hospital of Hunan Central South University in January 2017, Ganoderma Lucidum polysaccharides can alleviate the photoaging caused by ultraviolet rays, and its main mechanism and oxidation resistance are closely related.
The researchers obtained fibroblasts directly from humans, cultured them in vitro, allowed the cells to proliferate, and then established a photo-aging cell experimental model by ultraviolet B irradiation.
The fibroblasts located in the dermis are responsible for the production of collagen and elastic fibers, which are the source of the youthfulness of the skin. Therefore, the condition of the cells themselves and the substances secreted by the cells can reflect the severity of photoaging.
The experiment found that ultraviolet light can reduce the survival rate of human skin fibroblasts and increase aging cells, decrease the production of Type I collagen (collagens in the skin can be divided into three types, of which Type I accounts for more than 80%), increase the concentration of MMP-1 (type I matrix metalloproteinase) which breaks down the collagens, and raise the level of reactive oxygen species (ROS).
In contrast, human skin fibroblasts previously cultured with Reishi Mushroom polysaccharide GL-PS (with the dose of 10, 20 or 40 μg/mL) have a significantly reduced content of reactive oxygen species induced by the ultraviolet ray and have clearly weakened indexes associated with skin aging.
Ultraviolet rays kill human skin fibroblasts. At the same irradiation time (48 hours), the stronger the UVB irradiation dose is, the less the number of fibroblasts responsible for collagen production will be.
Ganoderma lucidum polysaccharide can reduce the killing power of ultraviolet rays on cells. Similarly, under the UVB radiation for 24 hours, the survival rate of human skin fibroblasts cultured with Ganoderma lucidum polysaccharide GL-PS is higher than that of the cells without GL-PS protection, even higher than the control group (not cultured with Ganoderma lucidum polysaccharides and without ultraviolet light irradiation).
Ganoderma lucidum polysaccharide can reduce cell aging caused by ultraviolet rays. The aging number of human skin fibroblasts cultured with Ganoderma lucidum polysaccharide GL-PS, which were also irradiated with UVB for 24 hours, is less than that of the cells without GL-PS protection.
Ganoderma lucidum polysaccharide can inhibit the induction of MMP-1 by ultraviolet light. MMP-1 can decompose collagen, and its concentration will increase due to ultraviolet UVB irradiation (24 hours), but Ganoderma lucidum polysaccharide GL-PS can slow down this condition and even make the MMP-1 concentration almost same with that of the control group (neither cultured with GL -PS nor receiving ultraviolet irradiation).
Ganoderma lucidum polysaccharide can reduce the damage to collagen by ultraviolet light. Collagen is an important element in maintaining young skin. Its concentration can be reduced by UVB exposure (24 hours), but Ganoderma lucidum polysaccharide GL-PS can improve this condition and even maintain the concentration of collagen almost same with that of the control group (neither cultured with GL-PS nor receiving UV irradiation).
Ganoderma lucidum polysaccharides can inhibit the formation of oxygen free radicals induced by ultraviolet irradiation. The reason why ultraviolet rays cause skin aging is closely related to the increase of reactive oxygen species. Ganoderma lucidum polysaccharide GL-PS can reduce the production of free radicals, and the effect is positively correlated with GL-PS dose.
This study shows that Lingzhi polysaccharides resist UV damage and reduce photoaging. Since this is the result of the direct action of Ganoderma lucidum polysaccharides on human skin fibroblasts, it highlights the potential of Ganoderma lucidum polysaccharides as skin care products. As long as the Ganoderma lucidum polysaccharide can be sent from the epidermis to the dermis to interact with the fibroblasts, it may be able to withstand the UV ray damage and keep the skin always young and healthy.
[Source] Zeng Q, et al. Ganoderma lucidum polysaccharides protect fibroblasts against UVB-induced photoaging. Mol Med Rep. 2017 Jan;15(1):111-116.