Hypericum olympicum L. recovers DNA damage and prevents MMP-9 activation induced by UVB in human dermal fibroblasts

ETHNOPHARMACOLOGICAL RELEVANCE

Hypericum olympicum L. (Hypericaceae) flowering aerial parts has been utilized in Turkish folk medicine as a remedy against inflamed skin problems.

AIM OF THE STUDY

This study was designed to state the effect of H. olympicum on dermatological problems. For this purpose effect of the plant extract on the DNA strand break and matrix metalloproteinase (MMP)-9 activity of human dermal fibroblast (HDFs) cells irradiated with UVB as well as antioxidant activity potential were studied.

MATERIALS AND METHODS

The methanolic extract of Hypericum olympicum (HOM) was prepared by maceration at room temperature. DNA damage and increased MMP-9 activity in HDFs were induced by UVB irradiation. The cell viability was measured by water-soluble tetrazolium salt (WST)-1 assay. The effects on DNA strand break was investigated by single gel electrophoresis (commonly known as Comet assay), while MMP-9 activity was observed by gelatin zymography assay. In vitro antioxidant tests were performed to indicate the effect on reactive oxygen species (ROS). The major metabolites were identified and their concentrations were measured by high performance thin layer chromatography (HPTLC).

RESULTS

HOM was found to recover DNA damage dose-dependently. The enzymatic activity of MMP-9 was inhibited almost 100% by the treatment of 1.5 mg/mL of the extract. It also enhanced cell proliferation in those cells, and also it was shown to possess antioxidant activity. The major metabolites of HOM were identified as chlorogenic acid and quercetin glycosides (rutin, hyperoside, isoquercitrin).

CONCLUSION

Experimental studies have proven the traditional use of Hypericum olympicum in inflamed skin problems acting by inhibition of the inflammatory pathway and recovery of DNA damage induced experimentally.

The Potential of Triterpenoids from Loquat Leaves (Eriobotrya japonica) for Prevention and Treatment of Skin Disorder

The leaves of loquat (Eriobotrya japonica) possess high medicinal value and have been used as traditional medicines. However, there are no evidence-based studies on the skin-care effects of E. japonica leaves. To explore new biological activities of E. japonica leaves against skin disorder and to gain a better understanding of the chemical components associated with bioactivities, we evaluated 18 triterpenoids from E. japonica leaves on anti-melanogenesis, anti-acne, anti-allergy and anti-aging activities. Our results revealed that eight compounds showed anti-melanogenesis activity, of which ursolic acid (1) and maslinic acid (7) were the most potent with the similar selective index to that of arbutin. Structure–activity relationship and possible mechanism of active compounds were proposed. Twelve compounds exhibited anti-acne effect; ursolic acid (1), maslinic acid (7), corosolic acid (8) and euscaphic acid (12) showed highest activities against P. acnes. Four compounds displayed anti-allergy and anti-inflammatory activity; 3-epicorosolic acid (9) and euscaphic acid (12) showed marked activity against β-hexosaminidase release. Finally, ursolic acid (1), pomolic acid (10), colosolic acid (8) and its methylated derivative (6) exhibited the highest anti-aging activity by stimulating collagen and hyaluronic acid (HA) production. Our findings provide valuable evidence that E. japonica leaves have potential applications as ingredients of function foods or cosmetics for health benefits and a number of triterpenoids may play an important role in these bioactivities.