Antiphotoaging Effects of Damiana (Turnera diffusa) Leaves Extract via Regulation AP-1 and Nrf2/ARE Signaling Pathways

Abstract

Damiana (Turnera diffusa), of the family Passifloraceae, has been widely studied for its pharmacological effects, especially for antioxidant and antibacterial actions. However, there are limited scientific findings describing its antiphotoaging effects on the skin. In the present study, the underlying molecular mechanisms of the protective effect of Damiana were investigated in keratinocytes (HaCaTs) and normal human dermal fibroblasts (HDFs) subject to UVB irradiation. The mRNA expression of matrix metalloproteinases (MMPs) and procollagen type I was determined by reverse transcription-polymerase chain reaction. The protein expression of antiphotoaging-related signaling molecules in the activator protein-1 (AP-1) and nuclear factor erythroid 2-related factor 2 (NRF2)/antioxidant response element (ARE) pathways was assessed by Western blotting. We observed that Damiana blocked the upregulated production of reactive oxygen species induced in UVB-irradiated HaCaTs and HDFs in a dose-dependent manner. Treatment with Damiana also significantly ameliorated the mRNA expression of MMPs and procollagen type I. In addition, the phosphorylation level of c-Jun and c-Fos was also decreased through the attenuated expression of p-38, p-ERK, and p-JNK after treatment with Damiana. Furthermore, the treatment of cells with Damiana resulted in the inhibition of Smad-7 expression in the TGF-β/Smad pathway and upregulated the expression of the Nrf2/ARE signaling pathway. Hence, the synthesis of procollagen type I, a precursor of collagen I, was promoted. Collectively, these results provide us with the novel insight that Damiana is a potential source of antiphotoaging compounds.

Antioxidant Activity According to the Planting Interval and Collecting Time of Rosa davurica

“…According to our comparison of the experimental results, the flavonoid contents of R. davurica bud and leaf extracts had no significant differences based on planting interval and harvest date. Kim et al's study observed that the flavonoid content of Turnera diffusa leaves was 108.8 mg QE/g extract [20]. Furthermore, Quyen et al observed that the polyphenol content of Centella asiatica ranged between 2.14 and 2.82 mg GAE/g extract [21].…”

Anti-Photoaging Effect of Phaseolus angularis L. Extract on UVB-Exposed HaCaT Keratinocytes and Possibilities as Cosmetic Materials

“…The Nrf2/ARE signaling pathway has been reported to be the key regulator response to oxidative stress, and a variety of natural products have been shown to promote the translocation of Nrf2 to the nucleus [ 21 ]. For example, damiana leaves extract was reported to protect against UVB-induced damage by regulating the AP-1 and Nrf2/ARE pathways in HaCaT cells [ 22 , 23 ]. To determine the antioxidant mechanisms activated by PASE, we analyzed the expression of antioxidant factors from the Nrf2/ARE signaling pathway in UVB-exposed HaCaT cells.…”

Modified Qing’e Formula protects against UV-induced skin oxidative damage via the activation of Nrf2/ARE defensive pathway

“…Excessive reactive oxygen species are produced during skin photoaging. When the body cannot remove ROS in time, the redox system will be unbalanced, causing oxidative damage to intracellular nucleic acids, lipids and proteins, eventually triggering apoptosis and skin tissue damage ( Fitsiou et al, 2021 ; Kim et al, 2022 ). Therefore, it is imperative to use safe and effective phytochemicals to protect the skin from these harmful effects.…”