Protective Effect of Sanguinarine on Ultraviolet B-mediated Damages in SKH-1 Hairless Mouse Skin: Implications for Prevention of Skin Cancer

The Synergistic Effect of Piperlongumine and Sanguinarine on the Non-Small Lung Cancer

BACKGROUND

Cancers are one of the leading causes of deaths nowadays. The development of new treatment schemes for oncological diseases is an interesting direction in experimental medicine. Therefore, the evaluation of the influence of two alkaloids-piperlongumine (PL), sanguinarine (SAN) and their combination-on the basic life processes of the A549 cell line was considered reasonable.

METHODS

The aim was achieved by analyzing the cytotoxic effects of PL and SAN and their combination in the ratio of 4:1 on the induction of cell death, changes in the distribution of cell cycle phases, reorganization of cytoskeleton and metastatic potential of A549 cells. The versatility of the applied concentration ratio was evaluated in terms of other cancer cell lines: MCF-7, H1299 and HepG2.

RESULTS

The results obtained from the MTT assay indicated that the interaction between the alkaloids depends on the concentration and type of cells. Additionally, the compounds and their combination did not exhibit a cytotoxic effect against normal cells. The combined effects of PL and SAN increased apoptosis and favored metastasis inhibition.

CONCLUSION

Selected alkaloids exhibit a cytotoxic effect on A549 cells. In turn, treatment with the combination of PL and SAN in a 4:1 ratio indicates a synergistic effect and is associated with an increase in the level of reactive oxygen species (ROS).

Repurposing of plant alkaloids for cancer therapy: Pharmacology and toxicology

Drug repurposing (or repositioning) is an emerging concept to use old drugs for new treatment indications. Phytochemicals isolated from medicinal plants have been largely neglected in this context, although their pharmacological activities have been well investigated in the past, and they may have considerable potentials for repositioning. A grand number of plant alkaloids inhibit syngeneic or xenograft tumor growth in vivo. Molecular modes of action in cancer cells include induction of cell cycle arrest, intrinsic and extrinsic apoptosis, autophagy, inhibition of angiogenesis and glycolysis, stress and anti-inflammatory responses, regulation of immune functions, cellular differentiation, and inhibition of invasion and metastasis. Numerous underlying signaling processes are affected by plant alkaloids. Furthermore, plant alkaloids suppress carcinogenesis, indicating chemopreventive properties. Some plant alkaloids reveal toxicities such as hepato-, nephro- or genotoxicity, which disqualifies them for repositioning purposes. Others even protect from hepatotoxicity or cardiotoxicity of xenobiotics and established anticancer drugs. The present survey of the published literature clearly demonstrates that plant alkaloids have the potential for repositioning in cancer therapy. Exploitation of the chemical diversity of natural alkaloids may enrich the candidate pool of compounds for cancer chemotherapy and -prevention. Their further preclinical and clinical development should follow the same stringent rules as for any other synthetic drug as well. Prospective randomized, placebo-controlled clinical phase I and II trials should be initiated to unravel the full potential of plant alkaloids for drug repositioning.

The Biological Activity of Natural Alkaloids against Herbivores, Cancerous Cells and Pathogens

The growing incidence of microorganisms that resist antimicrobials is a constant concern for the scientific community, while the development of new antimicrobials from new chemical entities has become more and more expensive, time-consuming, and exacerbated by emerging drug-resistant strains. In this regard, many scientists are conducting research on plants aiming to discover possible antimicrobial compounds. The secondary metabolites contained in plants are a source of chemical entities having pharmacological activities and intended to be used for the treatment of different diseases. These chemical entities have the potential to be used as an effective antioxidant, antimutagenic, anticarcinogenic and antimicrobial agents. Among these pharmacologically active entities are the alkaloids which are classified into a number of classes, including pyrrolizidines, pyrrolidines, quinolizidines, indoles, tropanes, piperidines, purines, imidazoles, and isoquinolines. Alkaloids that have antioxidant properties are capable of preventing a variety of degenerative diseases through capturing free radicals, or through binding to catalysts involved indifferent oxidation processes occurring within the human body. Furthermore, these entities are capable of inhibiting the activity of bacteria, fungi, protozoan and etc. The unique properties of these secondary metabolites are the main reason for their utilization by the pharmaceutical companies for the treatment of different diseases. Generally, these alkaloids are extracted from plants, animals and fungi. Penicillin is the most famous natural drug discovery deriving from fungus. Similarly, marines have been used as a source for thousands of bioactive marine natural products. In this review, we cover the medical use of natural alkaloids isolated from a variety of plants and utilized by humans as antibacterial, antiviral, antifungal and anticancer agents. An example for such alkaloids is berberine, an isoquinoline alkaloid, found in roots and stem-bark of Berberis asculin P. Renault plant and used to kill a variety of microorganisms.

Black salve treatment of skin cancer: a review

The use of complementary and alternative medicines in Australia has grown significantly. Much of this growth is due to their ease of accessibility from online vendors, often marketed with claims that are not scientifically tested. Black salve is a topical escharotic compound containing the active component sanguinarine, derived from the bloodroot plant. It has been advertised as a natural treatment for skin cancer. This article reviews the current state of black salve as an alternative skin cancer treatment, discussing its distribution and regulation, and provides a summary of clinical and laboratory studies. Clinical trials in this area are lacking, with most clinical data in the form of case reports demonstrating suboptimal therapeutic and cosmetic outcomes associated with its use. However, in vitro studies of sanguinarine suggest it causes indiscriminate destruction of healthy and cancerous tissue at doses higher than 5 µM, limiting its practical utility. It is vital that members of the public are aware of the potential effects and toxicity of commercial salve products.

Sanguinarine inhibits pancreatic cancer stem cell characteristics by inducing oxidative stress and suppressing sonic hedgehog-Gli-Nanog pathway

Sonic hedgehog pathway is highly activated in pancreatic cancer stem cells (CSC) which play crucial roles in cancer initiation, progression and metastasis. However, the molecular mechanisms by which sanguinarine regulates pancreatic CSC characteristics is not well understood. The objectives of this study were to examine the molecular mechanisms by which sanguinarine regulates pancreatic CSC characteristics. Sanguinarine inhibited cell proliferation and colony formation and induced apoptosis through oxidative damage. Sanguinarine inhibited self-renewal capacity of pancreatic CSCs isolated from human and KrasG12D mice. Furthermore, sanguinarine suppressed epithelial-mesenchymal transition (EMT) by up-regulating E-cadherin and inhibiting N-cadherin. Significant decrease in expression level of Snail, Slug and Zeb1 corroborated the suppression of EMT in sanguinarine treated pancreatic CSCS. The ability of sanguinarine to inhibit pluripotency maintaining factors and CSC markers suggest that sanguinarine can be an effective agent for inhibiting pancreatic cancer growth and development by targeting CSCs. Furthermore, sanguinarine inhibited Shh-Gli pathway leading to modulation of Gli target genes in pancreatic CSCs. Chromatin immunoprecipitation assay demonstrated that Nanog directly binds to promoters of Cdk2, Cdk6, FGF4, c-Myc and Oct4, and sanguinarine inhibits the binding of Nanog with these genes, suggesting the direct involvement of Nanog in cell cycle, pluripotency and self-renewal. To further investigate the role of Shh-Gli-Nanog pathway, we regulated Shh signaling either by Shh protein or Nanog overexpression. Enforced activation of Shh or overexpression of Nanog counteracted the inhibitory effects of sanguinarine on pancreatic CSC proliferation, suggesting the actions of sanguinarine are mediated, at least in part, through Shh-Gli-Nanog pathway. Our studies suggest that sanguinarine can be used for the treatment and/or prevention of pancreatic cancer by targeting CSCs.

Carcinogenic potential of sanguinarine, a phytochemical used in 'therapeutic' black salve and mouthwash

Black salves are escharotic skin cancer therapies in clinical use since the mid 19th century. Sanguinaria canadensis, a major ingredient of black salve formulations, contains a number of bioactive phytochemicals including the alkaloid sanguinarine. Despite its prolonged history of clinical use, conflicting experimental results have prevented the carcinogenic potential of sanguinarine from being definitively determined. Sanguinarine has a molecular structure similar to known polyaromatic hydrocarbon carcinogens and is a DNA intercalator. Sanguinarine also generates oxidative and endoplasmic reticulum stress resulting in the unfolded protein response and the formation of 8-hydroxyguanine genetic lesions. Sanguinarine has been the subject of contradictory in vitro and in vivo genotoxicity and murine carcinogenesis test results that have delayed its carcinogenic classification. Despite this, epidemiological studies have linked mouthwash that contains sanguinarine with the development of oral leukoplakia. Sanguinarine is also proposed as an aetiological agent in gallbladder carcinoma. This literature review investigates the carcinogenic potential of sanguinarine. Reasons for contradictory genotoxicity and carcinogenesis results are explored, knowledge gaps identified and a strategy for determining the carcinogenic potential of sanguinarine especialy relating to black salve are discussed. As patients continue to apply black salve, especially to skin regions suffering from field cancerization and skin malignancies, an understanding of the genotoxic and carcinogenic potential of sanguinarine is of urgent clinical relevance.

A Topical Zinc Ionophore Blocks Tumorigenic Progression in UV-exposed SKH-1 High-risk Mouse Skin

Nonmelanoma skin cancer (NMSC) is the most common malignancy in the United States representing a considerable public health burden. Pharmacological suppression of skin photocarcinogenesis has shown promise in preclinical and clinical studies, but more efficacious photochemopreventive agents are needed. Here, we tested feasibility of harnessing pharmacological disruption of intracellular zinc homeostasis for photochemoprevention in vitro and in vivo. Employing the zinc ionophore and FDA-approved microbicidal agent zinc pyrithione (ZnPT), used worldwide in over-the-counter (OTC) topical consumer products, we first demonstrated feasibility of achieving ZnPT-based intracellular Zn²⁺ overload in cultured malignant keratinocytes (HaCaT-ras II-4; SCC-25) employing membrane-permeable fluorescent probes. Zinc overload was accompanied by induction of intracellular oxidative stress, associated with mitochondrial superoxide release as substantiated by MitoSOX Red™ fluorescence microscopy. ZnPT-induced cell death observable in malignant keratinocytes was preceded by induction of metal (MT2A), proteotoxic (HSPA6, HSPA1A, DDIT3, HMOX1) and genotoxic stress response (GADD45A, XRCC2) gene expression at the mRNA and protein levels. Comet analysis revealed introduction of formamidopyrimidine-DNA glycosylase (Fpg)-sensitive oxidative DNA lesions. In a photocarcinogenesis model (UV-exposed SKH-1 high-risk mouse skin), topical ZnPT administration post-UV caused epidermal zinc overload and stress response gene expression with pronounced blockade of tumorigenesis. Taken together, these data suggest feasibility of repurposing a topical OTC drug for zinc-directed photochemoprevention of solar UV-induced NMSC.

Alleviation of Ultraviolet B-Induced Photodamage by Coffea arabica Extract in Human Skin Fibroblasts and Hairless Mouse Skin

Coffea arabica extract (CAE) containing 48.3 ± 0.4 mg/g of chlorogenic acid and a trace amount of caffeic acid was found to alleviate photoaging activity in human skin fibroblasts. In this study, polyphenol-rich CAE was investigated for its antioxidant and antiinflammatory properties, as well as for its capability to alleviate ultraviolet B (UVB)-induced photodamage in BALB/c hairless mice. The results indicated that 500 μg/mL of CAE exhibited a reducing power of 94.7%, ferrous ion chelating activity of 46.4%, and hydroxyl radical scavenging activity of 20.3%. The CAE dose dependently reduced UVB-induced reactive oxygen species (ROS) generation in fibroblasts. Furthermore, CAE inhibited the UVB-induced expression of cyclooxygenase-2 and p-inhibitor κB, and the translocation of nuclear factor-kappa B (NF-κB) to the nucleus of fibroblasts. In addition, CAE alleviated UVB-induced photoaging and photodamage in BALB/c hairless mice by restoring the collagen content and reduced UVB-induced epidermal hyperplasia. CAE also inhibited UVB-induced NF-κB, interleukin-6, and matrix metalloproteinase-1 expression in the hairless mouse skin. The results indicated that CAE exhibits antiphotodamage activity by inhibiting UV-induced oxidative stress and inflammation. Therefore, CAE is a candidate for use in antioxidant, antiinflammatory, and antiphotodamage products.

Sanguinaria canadensis: Traditional Medicine, Phytochemical Composition, Biological Activities and Current Uses

Sanguinaria canadensis, also known as bloodroot, is a traditional medicine used by Native Americans to treat a diverse range of clinical conditions. The plants rhizome contains several alkaloids that individually target multiple molecular processes. These bioactive compounds, mechanistically correlate with the plant’s history of ethnobotanical use. Despite their identification over 50 years ago, the alkaloids of S. canadensis have not been developed into successful therapeutic agents. Instead, they have been associated with clinical toxicities ranging from mouthwash induced leukoplakia to cancer salve necrosis and treatment failure. This review explores the historical use of S. canadensis, the molecular actions of the benzophenanthridine and protopin alkaloids it contains, and explores natural alkaloid variation as a possible rationale for the inconsistent efficacy and toxicities encountered by S.canadensis therapies. Current veterinary and medicinal uses of the plant are studied with an assessment of obstacles to the pharmaceutical development of S. canadensis alkaloid based therapeutics.

Role of Ultraviolet Radiation in Papillomavirus-Induced Disease

Human papillomaviruses are causally associated with 5% of human cancers. The recent discovery of a papillomavirus (MmuPV1) that infects laboratory mice provides unique opportunities to study the life cycle and pathogenesis of papillomaviruses in the context of a genetically manipulatable host organism. To date, MmuPV1-induced disease has been found largely to be restricted to severely immunodeficient strains of mice. In this study, we report that ultraviolet radiation (UVR), specifically UVB spectra, causes wild-type strains of mice to become highly susceptible to MmuPV1-induced disease. MmuPV1-infected mice treated with UVB develop warts that progress to squamous cell carcinoma. Our studies further indicate that UVB induces systemic immunosuppression in mice that correlates with susceptibility to MmuPV1-associated disease. These findings provide new insight into how MmuPV1 can be used to study the life cycle of papillomaviruses and their role in carcinogenesis, the role of host immunity in controlling papillomavirus-associated pathogenesis, and a basis for understanding in part the role of UVR in promoting HPV infection in humans.

Protection effect of sanguinarine on whole-body exposure of X radiation in BALB/c mice

To investigate the effects of sanguinarine (SAN) on acute radiation induced injury in mice, 45 mice were randomly divided into control, 10 Gy and SAN+10 Gy groups. Mice in the 10 Gy and SAN+10 Gy groups were exposed to single X-ray radiation with an accumulated dose of 10 Gy. Mice in the SAN+10 Gy group were administered intraperitoneally with 2.5 mg/kg body weight of SAN before radiation. Five days after radiation exposure, 5 mice from each group were sacrificed and samples of the small intestine, lung, spleen and liver were fixed for histopathological examinations. Compared with the 10 Gy group, radiation sickness was obviously delayed or attenuated in the SAN+10 Gy group. Survival analysis showed a significant difference between 2 radiation groups (P<0.05) and mean survival time was 3 days longer in the SAN+10 Gy group than in the 10 Gy group (7.21±0.19 vs. 4.20±0.13, P<0.001). Radiation-induced organ damage, based on histopathological examinations, was decreased by SAN pretreatment. Chiu’s pathology grading scores, which is an index of intestinal damage, was significantly lower in the SAN+10 Gy group than in the 10 Gy group (2.77±0.48 vs. 4.37±0.31, P<0.01). A similar result was obtained in the pathological score of lung (1.67±0.21 vs. 2.33±0.38, P<0.01). Our preliminary findings demonstrated that SAN protects animals against radiation-induced sickness and acute damage to organs and following animal death.

Dose-response on the chemopreventive effects of sarcophine-diol on UVB-induced skin tumor development in SKH-1 hairless mice

Sarcophine-diol (SD) is a lactone ring-opened analogue of sarcophine. It has shown chemopreventive effects on chemically-induced skin tumor development in female CD-1 mice, as well as in a UVB-induced skin tumor development model in hairless SKH-1 mice at a dose of 30 μg SD applied topically and 180 mJ/cm² UVB. The objective of this study was to determine the dose-response on the chemopreventive effects of SD on SKH-1 hairless mice when exposed to a UVB radiation dose of 30 mJ/cm². This UVB dose better represents chronic human skin exposure to sunlight leading to skin cancer than previous studies applying much higher UVB doses. Carcinogenesis was initiated and promoted by UVB radiation. Female hairless SKH-1 mice were divided into five groups. The control group was topically treated with 200 μL of acetone (vehicle), and the SD treatment groups were topically treated with SD (30 μg, 45 μg, and 60 μg dissolved in 200 μL of acetone) 1 h before UVB radiation (30 mJ/cm²). The last group of animals received 60 μg SD/200 μL acetone without UVB exposure. These treatments were continued for 27 weeks. Tumor multiplicity and tumor volumes were recorded on a weekly basis for 27 weeks. Weight gain and any signs of toxicity were also closely monitored. Histological characteristics and the proliferating cell nuclear antigen (PCNA) were evaluated in the mice skin collected at the end of the experiment. The dose-response study proved a modest increase in chemopreventive effects with the increase in SD dose. SD reduced the number of cells positively stained with PCNA proliferation marker in mice skin. The study also showed that SD application without UVB exposure has no effect on the structure of skin. The results from this study suggest that broader range doses of SD are necessary to improve the chemopreventive effects.

Alkaloids isolated from natural herbs as the anticancer agents

Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation and antimetastasis effects on various types of cancers both in vitro and in vivo. Alkaloids, such as camptothecin and vinblastine, have already been successfully developed into anticancer drugs. This paper focuses on the naturally derived alkaloids with prospective anticancer properties, such as berberine, evodiamine, matrine, piperine, sanguinarine, and tetrandrine, and summarizes the mechanisms of action of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as anticancer agents is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made.

Antitumor effects of the benzophenanthridine alkaloid sanguinarine in a rat syngeneic model of colorectal cancer

To evaluate the in-vivo preclinical antitumor activity of sanguinarine in a rat syngeneic model of colorectal cancer. The effects of sanguinarine on DHD/K12/TRb colorectal adenocarcinoma cells were first evaluated in vitro by means of ³H-thymidine incorporation, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay, and terminal transferase dUTP nick end labeling (TUNEL) microscopy. For the in-vivo studies, DHD/K12/TRb cells (1.5 × 10⁶ cells/0.3 ml of sterile saline/animal) were injected subcutaneously in syngeneic BDIX rats, which were chronically treated with sanguinarine (5 mg/kg/day per os) or control diluent. Tumor growth, body weight, hematologic, and clinical chemistry measurements were monitored in individual animals at defined time intervals. After killing, subcutaneous tumors were explanted from experimental animals for histopathological examination. In vitro, micromolar concentrations of sanguinarine inhibited dose-dependently DHD/K12/TRb cell proliferation and metabolism and induced cell death by apoptosis. In vivo, oral administration of sanguinarine induced a significant inhibition of tumor growth (P<0.01 vs. untreated controls), in the absence of any toxic or side effects. Marked apoptosis and reduced peritumoral vascularization were observed in tumors from sanguinarine-treated rats as compared with the controls. Additional basic studies are needed to fully characterize the mechanism/s underlying the inhibitory effects of sanguinarine on angiogenesis and tumor growth as well as the pharmacological and safety profile of this drug in experimental tumor models. Overall, findings from this study suggest that sanguinarine is a likely candidate for further evaluation in cancer therapy.

Expression and function of macrophage migration inhibitory factor in the pathogenesis of UV-induced cutaneous nonmelanoma skin cancer

Chronic skin exposure to ultraviolet light stimulates the production of cytokines known to be involved in the initiation of skin cancer. Recent studies in mouse models suggested a role for macrophage migration inhibitory factor (MIF) in the UVB-induced pathogenesis of nonmelanoma skin cancer (NMSC). Our studies aimed at defining the pathophysiological function of MIF in cutaneous inflammatory reactions and in the development and progression of NMSC. Immunohistochemical analysis revealed a moderate expression of MIF in normal human skin samples but an enhanced expression of this cytokine in lesional skin of patients with actinic keratosis or cutaneous SCC. Enzyme-linked immunosorbent assay studies showed a time-dependent increase in MIF secretion after a moderate single-dose UVB irradiation in NHEKs and SCC tumor cells. MIF is known to interact with CXCR2, CXCR4 and CD74. These receptors are not constitutively expressed in keratinocytes and HaCaT cells and their expression is not induced by UVB irradiation either. However, stimulation with IFNγ upregulated CD74 surface expression in these cells. Affymetrix(®) Gene Chip analysis revealed that only keratinocytes prestimulated with IFNγ are responsive to MIF. These findings indicate that MIF may be an important factor in the pathogenesis of NMSC tumorigenesis and progression in an inflammatory environment.

A mutant of SWAP-70, a phosphatidylinositoltrisphosphate binding protein, transforms mouse embryo fibroblasts, which is inhibited by sanguinarine

SWAP-70, a phosphatidylinositol trisphosphate (PtdIns(3,4,5)P₃) binding protein, has been suggested to be involved in transformation of mouse embryo fibroblasts (MEFs) as well as membrane ruffling after growth factor stimulation of the cells. A mutant, SWAP-70-374, was found to be able to bind to F-actin in vitro, whereas wild-type SWAP-70 failed to do so. This mutant was present at the plasma membrane without any stimulation while the wild-type protein was present only in the cytosol unless cells were stimulated with EGF. Expression of this mutant in MEFs resulted in morphologic transformation, fast growth, and loss of contact inhibition, suggesting that SWAP-70 with this mutation can transform the cells. ERK1/2 was activated in SWAP-70-374-transformed cells. Use of MEK inhibitors revealed that the ERK1/2 pathway does not affect the cell growth of MEFs but is responsible for loss of contact inhibition. To investigate the function of SWAP-70 further, drugs that can inhibit SWAP-70-dependent cell responses were screened. Among various drugs, sanguinarine was found to inhibit transformation of MEFs by SWAP-70-374. This drug was able to inhibit SWAP-70-mediated membrane ruffling as well, suggesting that its effect was closely related to the SWAP-70 signaling pathway. These results suggest that SWAP-70-374 can activate some signaling pathways, including the ERK1/2 pathway, to transform MEFs.

Dietary glucoraphanin-rich broccoli sprout extracts protect against UV radiation-induced skin carcinogenesis in SKH-1 hairless mice

Feeding broccoli sprout extracts providing daily doses of 10 micromol of glucoraphanin to SKH-1 hairless mice with prior chronic exposure to UV radiation (30 mJ cm(-2) of UVB, twice a week, for 17 weeks) inhibited the development of skin tumors during the subsequent 13 weeks; compared to the controls, tumor incidence, multiplicity, and volume were reduced by 25, 47, and 70%, respectively, in the animals that received the protective agent.

In vitro and in vivo anti-photoaging effects of an isoflavone extract from soybean cake

ETHNOPHARMACOLOGICAL RELEVANCE

Soy has been used in traditional Chinese medicine for thousands of years for its health and nutritional benefits, as well as to treat and care for the skin. Advanced skin care research has shown that soy isoflavone and genistein are effective in reducing damage to the skin from the sun.

AIM OF THE STUDY

To study the protective effects of isoflavone extract from soybean cake against the UVB-induced skin damage.

MATERIALS AND METHODS

The in vitro effects and possible mechanisms of soybean extract on UVB protection were determined in HaCaT cells. In the in vivo study, ICR-Foxn/(nu) mice were irradiated with UVB. The epidermal thickness, catalase and the expressions of cyclooxygenase-2 (COX-2) and proliferating cell nuclear antigen (PCNA) were detected to evaluate the antioxidant and anti-inflammatory activities of the isoflavone extract.

RESULTS

Our in vitro studies showed that UVB-induced HaCaT cell death and the phosphorylation of p38, JNK, and ERK1/2 decreased in the presence of isoflavone extract. In the in vivo studies, we found that the topical application of isoflavone extract before UVB irritation decreased the epidermal thickness and the expressions of COX-2 and PCNA and increased catalase concentration. These results showed anti-photoaging effect of isoflavone extract from soybean cake involved the inhibition of UVB-induced apoptosis and inflammation.

CONCLUSIONS

It is shown that isoflavone extract from soybean cake may be functional cosmeceutical candidate for skin photoaging.

Raman spectroscopic analysis of the increase of the carotenoid antioxidant concentration in human skin after a 1-week diet with ecological eggs

Skin aging is mainly caused by the destructive action of free radicals, produced by the UV light of the sun. The human skin has developed a protection system against these highly reactive molecules in the form of the antioxidative potential. Carotenoids are one of the main components of the antioxidants of the human skin. From former studies, it is known that skin aging is reduced in individuals with high levels of carotenoids. Because most of the antioxidants cannot be produced by the human organism, they must be up taken by nutrition. Using noninvasive Raman spectroscopic measurements it is demonstrated that not only fruits and vegetables but also eggs contain high concentrations of antioxidants including carotenoids, which are even doubled in the case of ecological eggs. After a 1-week diet with ecological eggs performed by six volunteers, it is found that the concentration of the carotenoids in the skin of the volunteers increased by approx. 20%. Our study does not intend to recommend exorbitant egg consumption, as eggs also contain harmful cholesterol. But in the case of egg consumption, ecological eggs from hens kept on pasture should be preferred to also receive a benefit for the skin.