Protective Effects of Euphrasia officinalis Extract against Ultraviolet B-Induced Photoaging in Normal Human Dermal Fibroblasts

Regulatory Mechanisms of Natural Active Ingredients and Compounds on Keratinocytes and Fibroblasts in Mitigating Skin Photoaging

Background

The mechanism underlying skin photoaging remains elusive because of the intricate cellular and molecular changes that contribute to this phenomenon, which have yet to be elucidated. In photoaging, the roles of keratinocytes and fibroblasts are vital for maintaining skin structure and elasticity. But these cells can get photo-induced damage during photoaging, causing skin morphological changes. Recently, the function of natural active ingredients in treating and preventing photoaging has drawn more attention, with researches often focusing on keratinocytes and fibroblasts.

Methods

We searched for studies published from 2007 to January 2024 in the Web of Science, PubMed, and ScienceDirect databases through the following keywords: natural plant, natural plant products or phytochemicals, traditional Chinese Medicine or Chinese herbal, plant extracts, solar skin aging, skin photoaging, and skin wrinkling. This review conducted the accordance of Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

Results

In total, 87 researches were included in this review (Figure 1). In keratinocytes, natural compounds may primarily regulate signal pathways such as the NF-κB, MAPK, PI3K/AKT, and Nrf2/ARE pathways, reducing inflammation and cellular damage, thus slowing skin photoaging. Additionally, in fibroblasts, natural active ingredients primarily promote the TGF-β pathway, inhibit MMPs activity, and enhance collagen synthesis while potentially modulating the mTOR pathway, thereby protecting the dermal collagen network and reducing wrinkle formation. Several trials showed that natural compounds that regulate keratinocytes and fibroblasts responses have significant and safe therapeutic effects.

Conclusion

The demand for natural product-based ingredients in sunscreen formulations is rising. Natural compounds show promising anti-photoaging effects by targeting cellular pathways in keratinocytes and fibroblasts, providing potential therapeutic strategies. However, comprehensive clinical studies are needed to verify their efficacy and safety in mitigating photoaging, which should use advanced pharmacological methods to uncover the complex anti-photoaging mechanisms of natural compounds.

Revealing the Phenolic Composition and the Antioxidant, Antimicrobial and Antiproliferative Activities of Two Euphrasia sp. Extracts

The species of the genus Euphrasia present important medicinal potential according to their traditional uses. However, few studies aim to sustain this fact by scientific evidence. The present study aimed to explore the phytochemical profile and investigate the antioxidant, antimicrobial and antiproliferative potential of E. officinalis subsp. pratensis Fr. (EO) and E. stricta J.P.Wolff ex J.F.Lehm (ES). The tested samples consisted of ethanolic extracts. The identification and quantification of phenolic compounds were performed using spectrophotometric and LC-MS/MS methods. The antioxidant capacity was evaluated using the DPPH, FRAP and xanthine oxidase methods. Antimicrobial properties were screened using disk diffusion, broth microdilution and anti-biofilm assays, while antiproliferative potential was assessed on a colorectal adenocarcinoma human cancer cell line (DLD-1). The LC-MS/MS analysis showed chlorogenic acid and rutin as the dominant constituents in the tested extracts. The antioxidant activity assays showed important capacity for both samples; in vitro antimicrobial and anti-biofilm properties were exhibited, especially against Gram-positive bacteria, and an important inhibitory potential was observed on the proliferation of the DLD-1 cell line. The findings in the present study contribute to the recommendation of EO and ES for the prevention and treatment of oxidative stress-related pathologies, cancer and microbial infections.

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

Phaseolus angularis L. is widely cultivated and is considered a superfood because of its nutritious protein and starch contents. Nevertheless, P. angularis's effects on skin photoaging are unknown. The aim of this study was to research the effects of P. angularis seed extract (PASE) on photoaging in human keratinocytes (HaCaT) damaged by UVB radiation so as to find out whether PASE can be used as an effective anti-photoaging ingredient in cosmetic products. The antioxidant activities were assessed using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radical scavenging, and reactive oxygen species (ROS) assays. Enzyme-linked immunosorbent assay (ELISA) analysis was used to determine the change in matrix metalloproteinase (MMP)-1, and MMP-3. The protein levels of mitogen-activated protein kinase (MAPK)/activator protein (AP)-1, transforming growth factor beta (TGF)-β/suppressor of mothers against decapentaplegic (Smad), and NF-E2-related factor (Nrf)2/antioxidant response element (ARE) were measured by western blot. As a result, PASE increased DPPH and ABTS antioxidant activities in a dose-dependent manner. Additionally, PASE treatment (100 µg/mL) significantly reverted the damage induced by UVB (125 mJ/cm²) irradiation by downregulating ROS, matrix metalloproteinase (MMP)-1, and MMP-3 secretion and expression and increasing procollagen type I production. To suppress MMP-1 and MMP-3 secretion, PASE significantly decreased UVB-induced p38 and JNK phosphorylation and phosphorylated c-Fos and c-Jun nuclear translocation. PASE promoted collagen I production by inhibiting UVB-induced TGF-β activation and Smad7 overexpression; antioxidant properties also arose from the stimulation of the Nrf2-dependent expression of the antioxidant enzymes heme oxygenase (HO)-1 and quinone oxidoreductase (NQO)-1. Our data demonstrated that PASE has the potential to prevent ROS formation induced by UVB exposure by targeting specific pathways. Thus, PASE might be a potent anti-photoaging component to exploit in developing anti-aging products.

Multispectroscopic, virtual and in vivo insights into the photoaging defense mediated by the natural food colorant bixin

An upsurge in early onset of photoaging due to repeated skin exposure to environmental stressors such as UV radiation is a challenge for pharmaceutical and cosmeceutical divisions. Current reports indicate severe side effects because of chemical or synthetic inhibitors of matrix metalloproteases (MMPs) in anti-skin aging cosmeceuticals. We evaluated the adequacy of bixin, a well-known FDA certified food additive, as a scavenger of free radicals and its inhibitory mechanism of action on MMP1, collagenase, elastase, and hyaluronidase. The anti-skin aging potential of bixin was evaluated by several biotechnological tools in silico, in vitro and in vivo. Molecular docking and simulation dynamics studies gave a virtual insight into the robust binding interaction between bixin and skin aging-related enzymes. Absorbance and fluorescence studies, enzyme inhibition assays, enzyme kinetics and in vitro bioassays of human dermal fibroblast (HDF) cells highlighted bixin's role as a potent antioxidant and inhibitor of skin aging-related enzymes. Furthermore, in vivo protocols were carried out to study the impact of bixin administration on UVA induced photoaging in C57BL/6 mice skin. Here, we uncover the UVA shielding effect of bixin and its efficacy as a novel anti-photoaging agent. Furthermore, the findings of this study provide a strong foundation to explore the pharmaceutical applications of bixin in several other biochemical pathways linked to MMP1, collagenase, elastase, and hyaluronidase.

Phenolic acids as chemotaxonomic markers able to differentiate the Euphrasia species

The objective of this study was to get the answer on the question, which phenolic compounds may serve as chemical markers in taxonomy of Euphrasia spp. (E. nemorosa, E. rostkoviana, E. stricta) collected from the wild. Moreover, it is still unknown how and which environmental parameters can impact on the quantity of polyphenols, flavonoids and phenolic acids. To the authors' knowledge, this is the first study that analyses such a broad spectrum of phenolic compounds in the genus Euphrasia and takes into account the habitat conditions of their synthesis. The species of Euphrasia differ significantly in the content of phenolic compounds. Euphrasia rostkoviana has the highest total content of polyphenols and flavonoids. Euphrasia stricta contains the largest amounts of phenolic acids, such as 5-O-caffeoylquinic, p-coumaric, protocatechuic and salicylic acid. It has been evidenced that the content of metabolites in the Euphrasia herb depends on a number of habitat parameters. The increased content of phenolic acids in E. stricta can be attributed to the fact that this species occupies drier habitats, with lower content of nitrogen and organic carbon compared to E. nemorosa and E. rostkoviana. The compounds that can be considered as chemotaxonomic markers are salicylic and protocatechuic acid for E. stricta, 5-O-caffeoylquinic acid for E. rostkoviana and ferulic acid for E. nemorosa. These findings provide theoretical and empirical basis for a chemotaxonomic classification of those species, which taken together with morphological characteristics should prevent misidentification.

Advantages of Hyaluronic Acid and Its Combination with Other Bioactive Ingredients in Cosmeceuticals

This study proposes a review on hyaluronic acid (HA) known as hyaluronan or hyaluronate and its derivates and their application in cosmetic formulations. HA is a glycosaminoglycan constituted from two disaccharides (N-acetylglucosamine and D-glucuronic acid), isolated initially from the vitreous humour of the eye, and subsequently discovered in different tissues or fluids (especially in the articular cartilage and the synovial fluid). It is ubiquitous in vertebrates, including humans, and it is involved in diverse biological processes, such as cell differentiation, embryological development, inflammation, wound healing, etc. HA has many qualities that recommend it over other substances used in skin regeneration, with moisturizing and anti-ageing effects. HA molecular weight influences its penetration into the skin and its biological activity. Considering that, nowadays, hyaluronic acid has a wide use and a multitude of applications (in ophthalmology, arthrology, pneumology, rhinology, aesthetic medicine, oncology, nutrition, and cosmetics), the present study describes the main aspects related to its use in cosmetology. The biological effect of HA on the skin level and its potential adverse effects are discussed. Some available cosmetic products containing HA have been identified from the brand portfolio of most known manufacturers and their composition was evaluated. Further, additional biological effects due to the other active ingredients (plant extracts, vitamins, amino acids, peptides, proteins, saccharides, probiotics, etc.) are presented, as well as a description of their possible toxic effects.

A novel amphibian-derived peptide alleviated ultraviolet B-induced photodamage in mice

Although the application potential of amphibian skin-derived active peptides in alleviating ultraviolet B (UVB)-induced damage has attracted increasing attention, research remains in its infancy. In this study, a new peptide (OM-GL15, GLLSGHYGRASPVAC) was identified from the skin of the green odorous frog (Odorrana margaretae). Results showed that OM-GL15 scavenged free radicals (2,2'-diazo-bis-3-ethylbenzothiazoline-6-sulfonic acid and 1,1-diphenyl-2-trinitrophenylhydrazine) and reduced Fe³⁺ to Fe²⁺. Moreover, topical administration of OM-GL15 significantly alleviated UVB-induced skin photodamage in mice. Exploration of the underlying mechanisms further showed that OM-GL15 exerted antioxidant potency. Specifically, the peptide reduced the levels of lipid peroxidation and malondialdehyde and protected epidermal cells from UVB-induced apoptosis by inhibiting DNA damage via down-regulation of p53, caspase-3, caspase-9, and Bax and up-regulation of Bcl-2. Our results highlight the potential application of amphibian skin-derived peptides in protection against UVB-induced photodamage and provide a novel peptide candidate for the development of anti-photodamage agents.

Peucedanum ostruthium Inhibits E-Selectin and VCAM-1 Expression in Endothelial Cells through Interference with NF-κB Signaling

Twenty natural remedies traditionally used against different inflammatory diseases were probed for their potential to suppress the expression of the inflammatory markers E-selectin and VCAM-1 in a model system of IL-1 stimulated human umbilical vein endothelial cells (HUVEC). One third of the tested extracts showed in vitro inhibitory effects comparable to the positive control oxozeaenol, an inhibitor of TAK1. Among them, the extract derived from the roots and rhizomes of Peucedanum ostruthium (i.e., Radix Imperatoriae), also known as masterwort, showed a pronounced and dose-dependent inhibitory effect. Reporter gene analysis demonstrated that inhibition takes place on the transcriptional level and involves the transcription factor NF-κB. A more detailed analysis revealed that the P. ostruthium extract (PO) affected the phosphorylation, degradation, and resynthesis of IκBα, the activation of IKKs, and the nuclear translocation of the NF-κB subunit RelA. Strikingly, early effects on this pathway were less affected as compared to later ones, suggesting that PO may act on mechanism(s) that are downstream of nuclear translocation. As the majority of cognate NF-κB inhibitors affect upstream events such as IKK2, these findings could indicate the existence of targetable signaling events at later stages of NF-κB activation.

Green synthesis of gold nanoparticles using Euphrasia officinalisleaf extract to inhibit lipopolysaccharide-induced inflammation through NF-κB and JAK/STAT pathways in RAW 264.7 macrophages

Background

Gold nanoparticles (AuNPs) have potential applications in the treatment and diagnosis process, which are attributed to their biocompatibility and high efficiency of drug delivery. In the current study, we utilized an extract of Euphrasia officinalis, a traditional folk medicine, to synthesize gold nanoparticles (EO-AuNPs), and investigated their anti-inflammatory effects on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.

Materials and methods

The AuNPs were synthesized from an ethanol extract of E. officinalis leaves and characterized using several analytical techniques. Anti-inflammatory activities of EO-AuNPs were detected by a model of LPS-induced upregulation of inflammatory mediators and cytokines including nitric oxide (NO), inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), IL-1β, and IL-6 in RAW 264.7 cells. The activation of nuclear factor (NF)-κB and Janus kinase/signal transducer and activators of transcription (JAK/STAT) signaling pathways was investigated by Western blot.

Results

The results confirmed the successful synthesis of AuNPs by E. officinalis. Transmission electron microscopy images showed obvious uptake of EO-AuNPs and internalization into intracellular membrane–bound compartments, resembling endosomes and lysosomes by RAW 264.7 cells. Cell viability assays showed that EO-AuNPs exhibited little cytotoxicity in RAW 264.7 cells at 100 µg/mL concentration after 24 hours. EO-AuNPs significantly suppressed the LPS-induced release of NO, TNF-α, IL-1β, and IL-6 as well as the expression of the iNOS gene and protein in RAW 264.7 cells. Further experiments demonstrated that pretreatment with EO-AuNPs significantly reduced the phosphorylation and degradation of inhibitor kappa B-alpha and inhibited the nuclear translocation of NF-κB p65. In addition, EO-AuNPs suppressed LPS-stimulated inflammation by blocking the activation of JAK/STAT pathway.

Conclusion

The synthesized EO-AuNPs showed anti-inflammatory activity in LPS-induced RAW 264.7 cells, suggesting they may be potential candidates for treating inflammatory-mediated diseases.