Plant Polyphenols Effectively Protect HaCaT Cells from Ultraviolet C-Triggered Necrosis and Suppress Inflammatory Chemokine Expression

Evaluation of the Anti-Inflammatory/Immunomodulatory Effect of Teucrium montanum L. Extract in Collagen-Induced Arthritis in Rats

The anti-inflammatory/immunomodulatory effects of Teucrium montanum L. (TM), a plant distributed in the Mediterranean region, have been insufficiently examined. The effects of the TM ethanol extract were tested in a rat collagen-induced arthritis (CIA) model of rheumatoid arthritis. LC-MS was used for the phytochemical analysis of the TM extract. Dark Agouti rats were immunized with bovine type II collagen (CII) in incomplete Freund's adjuvant for CIA, and treated with 100 or 200 mg/kg of TM extract daily via oral administration. Clinical and histopathological evaluations and a flow cytometric analysis of the phenotypic and functional characteristics of splenocytes and draining lymph node cells were performed. The cytokines in the paw tissue culture supernatants and anti-CII antibodies in serum were determined by ELISA. The TM extract, with the dominant components verbascoside and luteolin 7-O-rutinoside, reduced the arthritic score and ankle joint inflammation in CIA rats, promoted the antioxidant profile in serum, and lowered pro-inflammatory TNF-α, IL-6 and IL-1β production. It suppressed the activation status of CD11b+ cells by lowering CD86, MHCII and TLR-4 expression, and promoted the Th17/T regulatory cell (Tregs) balance towards Tregs. A lower frequency of B cells was accompanied by a lower level of anti-CII antibodies in treated rats. These findings imply the favorable effect of TM extract on the clinical presentation of CIA, suggesting its anti-inflammatory/immunomodulatory action and potential therapeutic effect.

Effect of verbascoside against acute kidney injury induced by rhabdomyolysis in rats

Rhabdomyolysis is a pathological condition caused by muscle tissue degradation. In this condition, intracellular contents enter the bloodstream, and acute kidney injury (AKI) develops. Verbascoside (VB) is one of the most common phenylethanoid glycosides and has antioxidant and anti-inflammatory effects. This study investigated the effects of VB on AKI induced by rhabdomyolysis in rats. Male Wistar rats were divided into six groups (n = 6): (1) control group (normal saline), (2) 50% glycerol (10 ml/kg, IM, single injection, only on the first day), (3)-(5) 50% glycerol (same as group 2) + VB (30, 60, and 100 mg/kg, IP, 4 days), and (6) VB (100 mg/kg). Serum and kidney tissue samples were collected on day 5. Subsequently, serum creatinine (Cr), blood urea nitrogen (BUN), renal glutathione (GSH), malondialdehyde (MDA), lipocalin associated with neutrophil gelatinase (NGAL), tumor necrosis factor-alpha (TNF-α), and pathological changes were investigated. The injection of glycerol elevated levels of kidney damage markers, including Cr and BUN in serum, MDA, TNF-α, and NGAL, along with a reduction in GSH levels in the kidney tissue. The administration of VB (100 mg/kg) significantly lowered the levels of these markers, indicating the therapeutic effect of VB against AKI caused by rhabdomyolysis. Histopathological examinations revealed enhanced myoglobin cast formation and tubular necrosis in the glycerol group, which was reduced in rats that received VB, although this reduction did not reach statistical significance. VB can reduce rhabdomyolysis-induced AKI through its anti-inflammatory and antioxidant effects and decrease kidney damage severity.

Verbascoside: comprehensive review of a phenylethanoid macromolecule and its journey from nature to bench

Polyphenolic compounds are among the most widely researched compounds for various therapeutic applications. However, naturally occurring phenylethanoid glycosides are least explored under this class of compounds. One such phenylethanoid glycoside, verbascoside (Vb), abundantly found among 200 species of 23 families, has gained recent attention due to its wide-spectrum therapeutic properties such as antioxidant, antimicrobial, anti-inflammatory, neuroprotective, cardioprotective, skin-protective, and anti-cancer. Despite having multiple therapeutic benefits, due to its large size, the compound has poor bioavailability for oral and topical applications. To meet these limitations, current research on Vb focuses on delivering it through nanoformulations. Presently, most developed formulations are liposome based for various applications, such as corneal epithelial wound healing, anti-neuropathic, anti-wrinkle, anti-hyperalgesia, atopic dermatitis, alopecia, and cutaneous wound healing. Multiple studies have confirmed the least acute and sub-acute toxicity for Vb. Few clinical studies have been performed for the therapeutic application of Vb to manage COVID-19, nephropathy, platelet aggregation, chronic primary glomerulonephritis, and acute hepatitis. Recent studies have shown the immense therapeutic potential of Vb in wound healing, dermatitis, neuroprotection, and anti-cancer activities, which creates a need for developing novel formulations for their respective uses. Long-term toxicity studies and techniques for scaling up Vb production by biotechnological approaches should be emphasized.

Polyphenols: Secondary Metabolites with a Biological Impression

Polyphenols are natural compounds which are plant-based bioactive molecules, and have been the subject of growing interest in recent years. Characterized by multiple varieties, polyphenols are mostly found in fruits and vegetables. Currently, many diseases are waiting for a cure or a solution to reduce their symptoms. However, drug or other chemical strategies have limitations for using a treatment agent or still detection tool of many diseases, and thus researchers still need to investigate preventive or improving treatment. Therefore, it is of interest to elucidate polyphenols, their bioactivity effects, supplementation, and consumption. The disadvantage of polyphenols is that they have a limited bioavailability, although they have multiple beneficial outcomes with their bioactive roles. In this context, several different strategies have been developed to improve bioavailability, particularly liposomal and nanoparticles. As nutrition is one of the most important factors in improving health, the inclusion of plant-based molecules in the daily diet is significant and continues to be enthusiastically researched. Nutrition, which is important for individuals of all ages, is the key to the bioactivity of polyphenols.

Molecular Mechanisms of Plant Extracts in Protecting Aging Blood Vessels

Plant Extracts (PE) are natural substances extracted from plants, rich in various bioactive components. Exploring the molecular mechanisms and interactions involved in the vascular protective effects of PE is beneficial for the development of further strategies to protect aging blood vessels. For this review, the content was obtained from scientific databases such as PubMed, China National Knowledge Infrastructure (CNKI), and Google Scholar up to July 2024, using the search terms "Plant extracts", "oxidative stress", "vascular aging", "endothelial dysfunction", "ROS", and "inflammation". This review highlighted the effects of PE in protecting aging blood vessels. Through pathways such as scavenging reactive oxygen species, activating antioxidant signaling pathways, enhancing respiratory chain complex activity, inhibiting mitochondrial-reactive oxygen species generation, improving nitric oxide bioavailability, downregulating the secretion of inflammatory factors, and activating sirtuins 1 and Nrf2 signaling pathways, it can improve vascular structural and functional changes caused by age-related oxidative stress, mitochondrial dysfunction, and inflammation due to aging, thereby reducing the incidence of age-related cardiovascular diseases.

Verbascoside Inhibits/Repairs the Damage of LPS-Induced Inflammation by Regulating Apoptosis, Oxidative Stress, and Bone Remodeling

Osteocytes play an important role as regulators of both osteoclasts and osteoblasts, and some proteins that are secreted from them play a role in bone remodeling and modeling. LPS affects bone structure because it is an inflammatory factor, despite verbascoside's potential for bone preservation and healing. Osteocytes may also be involved in the control of the bone's response to immunological changes in inflammatory situations. MLO-Y4 cells were cultured in either supplemented -MEM alone with a low serum to inhibit cell growth or media with LPS (10 ng/mL) and/or verbascoside (50 g/mL) to show the LPS effect. In our research, LPS treatment increased RANKL levels while decreasing OPG and RUNX2 expression. Treatment with verbascoside reduced RANKL expression. In our work, verbascoside increased the expression of OPG and RUNX2. In MLO-Y4 cells exposed to verbascoside, SOD, CAT, and GSH activities as well as the expression levels of bone mineralization proteins like PHEX, RUNX2, and OPG were all elevated.

A systematic review of natural products for skin applications: Targeting inflammation, wound healing, and photo-aging

BACKGROUND

Every day the skin is constantly exposed to several harmful factors that induce oxidative stress. When the cells are incapable to maintain the balance between antioxidant defenses and reactive oxygen species, the skin no longer can keep its integrity and homeostasis. Chronic inflammation, premature skin aging, tissue damage, and immunosuppression are possible consequences induced by sustained exposure to environmental and endogenous reactive oxygen species. Skin immune and non-immune cells together with the microbiome are essential to efficiently trigger skin immune responses to stress. For this reason, an ever-increasing demand for novel molecules capable of modulating immune functions in the skin has risen the level of their development, particularly in the field of natural product-derived molecules.

PURPOSE

In this review, we explore different classes of molecules that showed evidence in modulate skin immune responses, as well as their target receptors and signaling pathways. Moreover, we describe the role of polyphenols, polysaccharides, fatty acids, peptides, and probiotics as possible treatments for skin conditions, including wound healing, infection, inflammation, allergies, and premature skin aging.

METHODS

Literature was searched, analyzed, and collected using databases, including PubMed, Science Direct, and Google Scholar. The search terms used included "Skin", "wound healing", "natural products", "skin microbiome", "immunomodulation", "anti-inflammatory", "antioxidant", "infection", "UV radiation", "polyphenols", "polysaccharides", "fatty acids", "plant oils", "peptides", "antimicrobial peptides", "probiotics", "atopic dermatitis", "psoriasis", "auto-immunity", "dry skin", "aging", etc., and several combinations of these keywords.

RESULTS

Natural products offer different solutions as possible treatments for several skin conditions. Significant antioxidant and anti-inflammatory activities were reported, followed by the ability to modulate immune functions in the skin. Several membrane-bound immune receptors in the skin recognize diverse types of natural-derived molecules, promoting different immune responses that can improve skin conditions.

CONCLUSION

Despite the increasing progress in drug discovery, several limiting factors need future clarification. Understanding the safety, biological activities, and precise mechanisms of action is a priority as well as the characterization of the active compounds responsible for that. This review provides directions for future studies in the development of new molecules with important pharmaceutical and cosmeceutical value.

Spatial and Temporal Distribution of Phenolic and Flavonoid Compounds in Sour Jujube (Ziziphus. Acidojujuba Cheng et Liu) and Their Antioxidant Activities

In order to comprehensively analyze the antioxidant substances in sour jujube, total phenolic content (TPC) and total flavonoids contents (TFC) in different organs, including stem, leaf, flower, fruit pulp, and seed were analyzed for their contents and antioxidant activities. The results showed that leaves possessed significantly higher TPC and TFC (20.4 and 20.5 mg/g, respectively) than the other organs and have the highest antioxidant activity, which were also higher than the wild blueberry (A well-known for its high TPC). Subsequently, the variations in the antioxidant content and antioxidant activity of leaves were analyzed during leaf development. TPC in leaves sampled in may and august were significantly higher than that in other months, while the highest one was found in may. The n-hexane, ethyl acetate, n-butanol, and water fractions obtained from the main methanol extract of sour jujube leaves were evaluated for TPC and TFC and their antioxidant activity and it was found that ethyl acetate fraction displayed the highest TPC and TFC (184.5 and 193.3 mg/g, respectively), as well as the best antioxidant activity. In addition, using LC-MS and HPLC, ethyl acetate fraction was analyzed from qualitative and quantitative aspects; 31-one phenolic compounds, including catechin (33.0 mg/g), epigallocatechin (15.3 mg/g), quercetin 3-O-glucoside (11.4 mg/g), naringenin (6.7 mg/g), esculetin (4.8 mg/g), and chlorogenic acid (4.6 mg/g) were identified. Catechin, esculetin, epigallocatechin, chlorogenic acid, quercetin 3-O-glucoside, and naringenin exhibited high antioxidant activity. These results provide a theoretical basis for further study and utilization of flavonoid and polyphenols in sour jujube.

Skin Aging, Cellular Senescence and Natural Polyphenols

The skin, being the barrier organ of the body, is constitutively exposed to various stimuli impacting its morphology and function. Senescent cells have been found to accumulate with age and may contribute to age-related skin changes and pathologies. Natural polyphenols exert many health benefits, including ameliorative effects on skin aging. By affecting molecular pathways of senescence, polyphenols are able to prevent or delay the senescence formation and, consequently, avoid or ameliorate aging and age-associated pathologies of the skin. This review aims to provide an overview of the current state of knowledge in skin aging and cellular senescence, and to summarize the recent in vitro studies related to the anti-senescent mechanisms of natural polyphenols carried out on keratinocytes, melanocytes and fibroblasts. Aged skin in the context of the COVID-19 pandemic will be also discussed.

Potential of Olive Oil Mill Wastewater as a Source of Polyphenols for the Treatment of Skin Disorders: A Review

Current trends toward naturally occurring compounds of therapeutic interest have contributed to an increasing number of studies on olive oil phenolics in the treatment of diseases with oxidative and inflammatory origins. Recent focus has been on olive oil wastewater, which is richer in phenolic compounds than olive oil itself. In this review, we present findings demonstrating the potential use of olive mill wastewater in dermatology. Particular attention is given to compounds with proven benefits in topical pharmacology: caffeic and ferulic acids, tyrosol and hydroxytyrosol, verbascoside, and oleuropein. The review is divided into different sections: inflammatory skin diseases, microbial effects, wound healing in addition to the antimelanoma properties of olive mill waste phenolics, and their potential in sun protection agents. There is strong evidence to support further studies into the valorization of this abundant and sustainable source of phenolic compounds for use in dermatology and dermo-cosmetic preparations.

Radioprotective Role of Natural Polyphenols: From Sources to Mechanisms

The identification and development of radioprotective agents has emerged as a subject matter of research during recent years due to the growing usage of ionizing radiation in different areas of human life. Previous work on synthetic radioprotectors has achieved limited progress because of the numerous issues associated with toxicity. Compounds extracted from plants have potential to serve as lead candidates for developing ideal radioprotectors due to their low cost, safety and selectivity. Polyphenols are the most abundant and commonly dispersed group of biologically active molecules possessing broad range of pharmacological activities. Polyphenols have displayed efficacy for radioprotection during various investigations and can be administered at high doses with lesser toxicity. Detoxification of free radicals, modulating inflammatory responses, DNA repair, stimulation of hematopoietic recovery, and immune functions are the main mechanisms for radiation protection with polyphenols. Epicatechin, epigallocatechin-3-gallate, apigenin, caffeic acid phenylethylester, and silibinin provide cytoprotection together with the suppression of many pro-inflammatory cytokines owing to their free radical scavenging, anti-oxidant, and anti-inflammatory properties. Curcumin, resveratrol, quercetin, gallic acid, and rutin's radioprotective properties are regulated primarily by direct or indirect decline in cellular stress. Thus, polyphenols may serve as potential candidates for radioprotection in the near future, however, extensive investigations are still required to better understand their protection mechanisms.

Photoprotective Activity of Buddleja cordata Cell Culture Methanolic Extract on UVB-irradiated 3T3-Swiss Albino Fibroblasts

The research on compounds exhibiting photoprotection against ultraviolet radiation (UVR) is a matter of increasing interest. The methanolic extract of a cell culture of Buddleja cordata has potential photoprotective effects as these cells produce phenolic secondary metabolites (SMs). These metabolites are attributed with biological activities capable of counteracting the harmful effects caused by UVR on skin. In the present work, the methanolic extract (310–2500 µg/mL) of B. cordata cell culture showed a photoprotective effect on UVB-irradiated 3T3-Swiss albino fibroblasts with a significant increase in cell viability. The greatest photoprotective effect (75%) of the extract was observed at 2500 µg/mL, which was statistically comparable with that of 250 µg/mL verbascoside, used as positive control. In addition, concentrations of the extract higher than 2500 µg/mL resulted in decreased cell viability (≤83%) after 24 h of exposure. Phytochemical analysis of the extract allowed us to determine that it was characterized by high concentrations of total phenol and total phenolic acid contents (138 ± 4.7 mg gallic acid equivalents and 44.01 ± 1.33 mg verbascoside equivalents per gram of extract, respectively) as well as absorption of UV light (first and second bands peaking at 294 and 330 nm, respectively). Some phenylethanoid glycosides were identified from the extract.

Protective Effects of Ocimum gratissimumAqueous Extracts on HaCaT Cells Against UVC-Induced Inhibition of Cell Viability and Migration

Ultraviolet C (UVC) has been applied to treatment of infections in wounds for at least the last two decades, however, cells being treated can be damaged if exposure is prolonged, which calls for protective measures, such as drug or herbal pre-treatment, to minimize damage. Ocimum gratissimum contains plant polyphenols such as isoflavones and caffeic acid, which have antioxidant effects. We hypothesize that Ocimum gratissimum aqueous extracts (OGE) can inhibit UVC-induced oxidative damage on skin cells. In this study, HaCaT skin cells are used to test the protective effects of OGE on cell proliferation and migration after exposure to UVC radiation. Pretreatment with OGE (50~150μg/mL) before 40 J/m² UVC exposure was able to restore survival from 32.25% to between 46.77% and 68.00%, and 80 J/m² UVC exposure from 11.49% to between 19.07% and 43.04%. Morphological observation of primarily apoptotic cell death confirms the above findings. The flow cytometry analysis revealed that UVC increased the number of cells at the sub-G1 phase in a dose dependent manner, and when pre-treated with OGE the changes were partially reversed. Moreover, the wound healing test for observing migration showed that UVC 40-80 J/m² decreased cell migration to 47-28% activity and 100 μg/mL OGE was able to restore cell activity to81-69% at day 3. Based on the above results, we suggest that OGE has a protective effect on UVC-induced inhibition of cell proliferation and migration of skin cells and thus has potential application in wound care.

Biological effects of verbascoside and its anti-inflammatory activity on oral mucositis: a review of the literature

Oral mucositis is among the most common tissue toxicities associated with both cytotoxic cancer regimens and head and neck radiotherapy. Current management of oral mucositis might comprise growth factors and cytokines, anti-inflammatory agents, anesthetics, analgesics, antimicrobial and coating agents, cryotherapy and mucosal protectants. Despite its long history and its impact on patients, there are currently no effective options for the prevention or treatment of mucositis. In recent years, more attention has been focused on the role of natural drugs. Verbascoside belongs to the phenylpropanoid glycosides family. Several biological properties have been described, such as anti-inflammatory, antimicrobial, antitumor and antioxidant. Verbascoside, particularly when in solution with polyvinylpyrrolidone and sodium hyaluronate, thanks to barrier effect, is useful in re-epithelialization and in reducing pain, oral mucositis score, burning and erythema.

Estimation of phenolic compounds content and antioxidant activity of leaves extracts of some selected non-traditional plants

The aim of the research is the determination of the total antioxidant activity and the content of phenolic compounds of the leaves of 12 species of non-traditional plants, namely, Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem., Aronia mitschurinii A.K. Skvortsov & Maitul., Castanea sativa Mill., Chaenomeles japonica (Thunb.) Lindl., Cornus mas L., Diospyros kaki L., Diospyros lotus L., Diospyros virginiana L., Lycium barbarum L., Lycium сhinense Mill., Pseudocydonia sinensis (Thouin) C.K. Schneid., Ziziphus jujuba Mill. Total phenolic content was evaluated using the Folin-Ciocalteu reagent assay. Antioxidant activity was measured using two different methods (DPPH – 2,2-diphenyl-1-picrylhydrazyl, MRAP – molybdenum reducing antioxidant power). Significant variability was observed in phenolic compounds content and total antioxidant activity. Total polyphenol content ranged from 38.02 (Z. jujuba) to 80.58 (C. sativa) mg GAE.g-1 DM, total flavonoid content from 22.47 (P. sinensis) to 54.61 (L. barbarum) mg QE.g-1 DM and phenolic acids content from 3.51 (A. mitschurinii) to 24.67 (Ch. japonica) mg CAE.g-1 DM. All tested samples exhibited DPPH• radical scavenging activities with values from 6.92 (A. mitschurinii) to 9.0 (C. mas) mg TEAC.g-1 DM. Antioxidant activity by molybdenum reducing antioxidant power method ranged from 109.43 (A. mitschurinii) to 322.95 (C. mas) mg TEAC.g-1 DM. Differences between the species of non-traditional plants were significant in all observed parameters. Obtained results of phytochemical composition demonstrated the possibility of leaves' use of non-traditional plants as sources of valuable bioactive compounds with health-promoting and disease-preventing properties.

Impact of polyphenols in phagocyte functions

Polyphenols are a broad group of substances with potential health benefits found in plant species. Several of these compounds are capable of influencing the activation of intracellular signaling pathways, such as NF-kB, MAPK and JAK-STAT, responsible for the production of various inflammatory mediators such as tumor necrosis factor α (TNF-α) and interleukin 1 beta (IL-1β) and 12 (IL-12), enzymes involved in the production of reactive species such as inducible nitric oxide synthase (iNOS) and superoxide dehydrogenase (SOD), as well as enzymes involved in the production of eicosanoids, such as cyclooxygenase (COX) and lipoxygenase (LO). There is increased interest in the use of polyphenol-rich foods because of their immunomodulatory effect; however, the mechanisms used during macrophage responses are extremely complex and little is known about the effects of polyphenols on these cells. As such, this review summarizes the current view of polyphenol influences on macrophages.

Dietary Biotechnological Ajuga reptans Extract in Post Weaning Piglets: Effects on Growth Performance, Oxidative Status and Immune Parameters

The effect of dietary supplementation with a biotechnological extract of Ajuga reptans on growth performance, oxidative status and immune parameters was evaluated in post weaning piglets. At weaning, 120 piglets with an average live weight of 8.1±1.3 kg, were assigned to one of three experimental groups. The first group was fed a control diet (C). The second and third groups were fed the same diet supplemented with 5 mg (T1) and 10 mg (T2) of teupolioside/kg feed from a biotechnological plant extract. Growth performances were recorded and blood samples were collected at the beginning, at 14 days, and at the end of the trial (56 days). Serum biochemical parameters, oxidative status and immunoglobulin titres were determined. Average daily gain tended to be higher (P=0.057) and live weight was higher in piglets (P<0.05) fed with different amounts of plant extract (T1 and T2) than the controls. The production of reactive oxygen metabolites (ROMs) was higher (P<0.05) in the control group than in the groups receiving teupolioside (T1 and T2). Concentration of serum immunoglobulin of class G improved (P<0.001) in piglets fed the T1 and T2 diets than the controls. Overall, the results suggested that the biotechnological extract of Ajuga reptans containing teupolioside has an antioxidant and immunomodulant effect.

Protective Effect of Acteoside on Ovariectomy-Induced Bone Loss in Mice

Acteoside, an active phenylethanoid glycoside compound isolated from herbs of Cistanche, was chosen for the investigation of anti-osteoporotic effect on postmenopausal osteoporosis by using an ovariectomized (OVX) mice model. The results from in vivo experiments showed that after daily oral administration of acteoside (20, 40, and 80 mg/kg body weight/day) for 12 weeks, bone mineral density and bone biomechanical properties of OVX mice were greatly enhanced, with significant improvement in bone microarchitecture. Furthermore, biochemical parameters of bone resorption markers as well as bone formation index, including tartrate-resistant acid phosphatase, cathepsin K, deoxypyridinoline, alkaline phosphatase, and bone gla-protein, were ameliorated by acteoside treatment, whereas the body, uterus, and vagina wet weights were seemingly not impacted by acteoside administration. Acteoside significantly affected osteoclastogenesis by attenuating nuclear factor kappa B (NF-κB) and stimulating phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signal pathways through down-regulated levels of tumor-necrosis factor receptor-associated factor 6 (TRAF6), receptor activator of nuclear factor kappa B ligand (RANKL), RANK, NFKBIA, IκB kinase β, nuclear factor of activated T-cells c2 (NFAT2), and up-regulated expressions of PI3K, AKT, and c-Fos. Accordingly, the current research validated our hypothesis that acteoside possesses potent anti-osteoporotic properties and may be a promising agent for the prevention of osteoporosis in the future.

ES2 as a Novel Verbascoside-Derived Compound in the Treatment of Cutaneous Wound Healing

Several pathologies are characterized by chronic wounds and often resistant to many of the common therapies, leading to chronic infections that can become even life-threatening for patients. For this reason, the identification of new products able to ameliorate the healing process is still an on-going research. Natural compounds have been used to improve skin conditions due to their dermo-cosmetic and therapeutic activities including anti-inflammatory, antioxidant and cell-migratory properties. Among these compounds, it has been recently demonstrated that Verbascoside, a phenyl propanoid glycoside widely used in the cosmetic field, can improve keratinocytes proliferation. Because of its high hydrophilic character, Verbascoside has a limited range of possible topical applications and the synthesis of ES2, a semi-synthetic derivative of Verbascoside was performed to bypass some of the drawback aspects of this molecule. In the present study, the wound healing properties of Verbascoside and ES2 were compared in both keratinocytes “in vitro” wound scratch and in wounded SKH1 mice. The results showed that both compounds were not cytotoxic and ES2 showed an efficient ability to promote the proliferation of human keratinocytes compared to Verbascoside. The findings were also confirmed in vivo but only at early time points (2/3 days). Taken together, these data suggest that the Verbascoside-derivative ES2 could be considered a novel and promising candidate for the topical treatment of wounds.

Ethanolic Extract of Origanum vulgare Suppresses Propionibacterium acnes-Induced Inflammatory Responses in Human Monocyte and Mouse Ear Edema Models

Acne vulgaris (acne) is a common inflammatory skin disorder, and Propionibacterium acnes plays a major role in the development and progression of acne inflammation. Herbs possessing antimicrobial and anti-inflammatory activity have been applied as a medical option for centuries. In this study, we examined the suppressive effect of ethanolic oregano (Origanum vulgare) extract on live P. acnes-induced in vivo and in vitro inflammation. Following ethanol extraction of oregano leaves, four compounds with strong antioxidant activity, including rosmarinic acid, quercetin, apigenin, and carvacrol, were identified by high-performance liquid chromatography. Using the mouse ear edema model, we demonstrated that ethanol oregano extracts (EOE) significantly suppressed P. acnes-induced skin inflammation, as measured by ear thickness (32%) and biopsy weight (37%). In a separate study, using the co-culture of P. acnes and human THP-1 monocytes, EOE reduced the production of interleukin (IL)-8, IL-1β and tumor necrosis factor (TNF)-α up to 40%, 37%, and 18%, respectively, as well as the expression of these three pro-inflammatory mediators at the transcriptional level. Furthermore, EOE inhibited the translocation of nuclear factor-kappa B (NF-κB) into the nucleus possibly by inactivating toll-like receptor-2 (TLR2). The suppressive effect of EOE on live P. acnes-induced inflammatory responses could be due, in part, to the anti-inflammatory and antioxidant properties, but not the anti-microbial effect of EOE.

Determination of the Phenolic Composition and Antioxidant Activity of Pear Extracts

The specific HPLC analytical procedure was developed and validated for the determination of phenolic compounds in pear samples of different popular cultivars “Conference,” “Concordia,” “Grabova,” and “Patten.” HPLC mobile phase consisted of 0.05% (v/v) trifluoroacetic acid in water and 100% (v/v) acetonitrile. The HPLC method was used to identify and confirm the specificity of 8 analytes: chlorogenic acid, rutin, hyperoside, isoquercitrin, isorhamnetin rutinoside, quercitrin, quercitrin malonyl glucoside, and isorhamnetin glucoside. Repeatability % RSD did not exceed 3.87%, and intermediate precision did not exceed 4.63%. The total content of phenolic compounds varied from0.51±0.001 mg/g (cv. “Concordia”) to1.11±0.013 mg/g (cv. “Patten”). Chlorogenic acid was the major component in all the tested pear cultivars. The highest amount of chlorogenic acid (0.69±0.033 mg/g) was found in pear samples of the cultivar “Grabova,” and the highest amount of flavonol compounds (1.11±0.013 mg/g) was found in pear samples of the cultivar “Concordia.”

Djulis (Chenopodium formosanum Koidz.) Water Extract and Its Bioactive Components Ameliorate Dermal Damage in UVB-Irradiated Skin Models

Dermal photoaging is a condition of skin suffering inappropriate ultraviolet (UV) exposure and exerts inflammation, tissue alterations, redness, swelling, and uncomfortable feelings. Djulis (Chenopodium formosanum Koidz.) is a cereal food and its antioxidant and pigment constituents may provide skin protection from photoaging, but it still lacks proved experiments. In this study, protective effects of djulis extract (CFE) on UVB-irradiated skin were explored. The results showed that HaCaT cells with 150 μg/mL CFE treatment had higher survival and less production of interleukin- (IL-) 6, matrix metalloprotease- (MMP-) 1, and reactive oxygen species (ROS) in UVB-irradiated conditions. Subsequently, in animal studies, mice supplemented with CFE (100 mg/kg BW) were under UVB irradiation and had thinner epidermis and lower IL-6 levels in skin layer. These data demonstrate that bioactive compounds possessing the potency of antiphotoaging exist in CFE. Following that, we found rutin and chlorogenic acid (10-100 μM) could significantly increase cell viability and decrease the production of IL-6 in UVB models. Additionally, djulis pigment-betanin has no effect of increasing cell viability in this study. Our findings suggest CFE can protect skin against UV-induced damage and this protection is mainly from contributions of rutin and chlorogenic acid.

The Potential of Plant Phenolics in Prevention and Therapy of Skin Disorders

Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract.

Screening of Panamanian Plants for Cosmetic Properties, and HPLC-Based Identification of Constituents with Antioxidant and UV-B Protecting Activities

A library of 600 taxonomically diverse Panamanian plant extracts was screened for DPPH scavenging and UV-B protective activities, and the methanolic extracts of Mosquitoxylum jamaicense, Combretum cacoucia, and Casearia commersionia were submitted to HPLC-based activity profiling. The compounds located in the active time windows were isolated and identified as gallic acid derivatives and flavonoids. Gallic acid methyl ester (3) and digallic acid derivatives (2, 6) showed the highest DPPH scavenging activity (<10 μg/mL), while protocatechuic acid (7) and isoquercitrin (10) exhibited the highest UV-B protective properties.

Verbascoside--a review of its occurrence, (bio)synthesis and pharmacological significance

Phenylethanoid glycosides are naturally occurring water-soluble compounds with remarkable biological properties that are widely distributed in the plant kingdom. Verbascoside is a phenylethanoid glycoside that was first isolated from mullein but is also found in several other plant species. It has also been produced by in vitro plant culture systems, including genetically transformed roots (so-called 'hairy roots'). Verbascoside is hydrophilic in nature and possesses pharmacologically beneficial activities for human health, including antioxidant, anti-inflammatory and antineoplastic properties in addition to numerous wound-healing and neuroprotective properties. Recent advances with regard to the distribution, (bio)synthesis and bioproduction of verbascoside are summarised in this review. We also discuss its prominent pharmacological properties and outline future perspectives for its potential application.

Quercetin-3-O-(2″-galloyl)-α-l-rhamnopyranoside inhibits TNF-α-activated NF-κB-induced inflammatory mediator production by suppressing ERK activation

Quercetin and its derivatives have anti-inflammatory and anti-oxidant effects. However, the effect of quercetin-3-O-(2″-galloyl)-α-l-rhamnopyranoside (QGR), a new quercetin derivative, on the tumor necrosis factor (TNF)-α-stimulated production of inflammatory mediators in keratinocytes is unclear. In addition, the effect of QGR on the ERK and NF-κB-mediated inflammatory process has not been studied. In human keratinocyte HaCat cells, we investigated the effect of QGR on the TNF-α-stimulated production of inflammatory mediators in relation to the nuclear factor (NF)-κB, which regulates the transcription genes involved in immune and inflammatory responses. QGR inhibited the TNF-α-stimulated production of cytokines and chemokines in HaCaT cells. QGR, dexamethasone, cyclosporine A, Bay 11-7085 (an inhibitor of NF-κB activation) and cell signaling ERK inhibitor attenuated the TNF-α-induced formation of inflammatory mediators and activation of the NF-κB and ERK. Unlike other compounds, dexamethasone and cyclosporine A did not reduce formation of reactive oxygen species. The results show that QGR may attenuate TNF-α-stimulated inflammatory mediator production in HaCaT cells by suppressing the activation of the ERK-mediated NF-κB pathway that is mediated by reactive oxygen species. Additionally, QGR may exhibit a preventive effect against the proinflammatory mediator-induced skin diseases by inhibiting the activation of the ERK and NF-κB pathways.

An Endogenous Electron Spin Resonance (ESR) signal discriminates nevi from melanomas in human specimens: a step forward in its diagnostic application

Given the specific melanin-associated paramagnetic features, the Electron Spin Resonance (ESR, called also Electron Paramagnetic Resonance, EPR) analysis has been proposed as a potential tool for non-invasive melanoma diagnosis. However, studies comparing human melanoma tissues to the most appropriate physiological counterpart (nevi) have not been performed, and ESR direct correlation with melanoma clinical features has never been investigated. ESR spectrum was obtained from melanoma and non-melanoma cell-cultures as well as mouse melanoma and non-melanoma tissues and an endogenous ESR signal (g = 2.005) was found in human melanoma cells and in primary melanoma tissues explanted from mice, while it was always absent in non-melanoma samples. These characteristics of the measured ESR signal strongly suggested its connection with melanin. Quantitative analyses were then performed on paraffin-embedded human melanoma and nevus sections, and validated on an independent larger validation set, for a total of 112 sections (52 melanomas, 60 nevi). The ESR signal was significantly higher in melanomas (p = 0.0002) and was significantly different between “Low Breslow’s and “High Breslow’s” depth melanomas (p<0.0001). A direct correlation between ESR signal and Breslow’s depth, expressed in millimetres, was found (R = 0.57; p<0.0001). The eu/pheomelanin ratio was found to be significantly different in melanomas “Low Breslow’s” vs melanomas “High Breslow’s” depth and in nevi vs melanomas “High Breslow’s depth”. Finally, ROC analysis using ESR data discriminated melanomas sections from nevi sections with up to 90% accuracy and p<0.0002. In the present study we report for the first time that ESR signal in human paraffin-embedded nevi is significantly lower than signal in human melanomas suggesting that spectrum variations may be related to qualitative melanin differences specifically occurring in melanoma cells. We therefore conclude that this ESR signal may represent a reliable marker for melanoma diagnosis in human histological sections.

Phenylpropanoid glycosides from plant cell cultures induce heme oxygenase 1 gene expression in a human keratinocyte cell line by affecting the balance of NRF2 and BACH1 transcription factors

Phenylpropanoids have several highly significant biological properties in both plants and animals. Four phenylpropanoid glycosides (PPGs), verbascoside (VB), forsythoside B (FB), echinacoside (EC) and campneoside I (CP), were purified and tested for their capability to activate NRF2 and induce phase II cytoprotective enzymes in a human keratinocyte cell line (HaCaT). All four substances showed similar strong antioxidant and radical-scavenging activities as determined by diphenylpicrylhydrazyl assay. Furthermore, in HaCaT cells, FB and EC are strong activators of NRF2, the nuclear transcription factor regulating many phase II detoxifying and cytoprotective enzymes, such as heme oxygenase 1 (HMOX1). In HaCaT cells, FB and EC (200 μM) induced nuclear translocation of NRF2 protein after 24 h and reduced nuclear protein levels of BACH1, a repressor of the antioxidant response element. FB and EC greatly HMOX1 mRNA levels by more than 40-fold in 72 h. Cytoplasmic HMOX1 protein levels were also increased at 48 h after treatment. VB was less active compared to FB and EC, and CP was slightly active only at later times of treatment. We suggest that hydroxytyrosol (HYD) could be a potential bioactive metabolite of PPGs since HYD, in equimolar amounts to PGGs, is able to both activate HO-1 transcription and modify Nrf2/Bach1 nuclear protein levels. This is in agreement with the poor activity of CP, which contains a HYD moiety modified by an O-methyl group. In conclusion, FB and EC from plant cell cultures may provide long-lasting skin protection by induction of phase II cytoprotective capabilities.

Plant polyphenols regulate chemokine expression and tissue repair in human keratinocytes through interaction with cytoplasmic and nuclear components of epidermal growth factor receptor system

AIMS

To evaluate mechanisms underlying modulation of inflammatory chemokines in primary human keratinocytes (normal human epidermal keratinocytes) and repair-related processes in wound models by plant polyphenols (PPs) with antioxidant and superoxide scavenging properties (verbascoside [Vb], resveratrol [Rv], polydatin [Pd], quercetin [Qr], and rutin).

RESULTS

Epidermal growth factor receptor (EGFR)-controlled chemokines CXCL8/interleukin 8 (IL-8), CCL2/monocyte chemotactic protein-1 (MCP-1), and CXCL10/interferon gamma-produced protein of 10 kDa (IP-10) were modulated by transforming growth factor alpha (TGF-α) and by the tumor necrosis factor alpha/interferon gamma combination (T/I). EGFR phosphorylation, nuclear translocation, and downstream cytoplasmic signaling pathways (extracellular regulation kinase [ERK]1/2, p38, STAT3, and PI-3K) were studied. All PPs did not affect TGF-α-induced STAT3 phosphorylation, whereas they suppressed T/I-activated NFkappaB and constitutive and T/I-induced but not TGF-α-induced ERK1/2 phosphorylation. Vb and Qr suppressed total EGFR phosphorylation, but they synergized with TGF-α to enhance nuclear accumulation of phosphorylated EGFR. Vb strongly inhibited TGF-α-induced p38 phosphorylation and T/I-induced NFkappaB and activator protein-1 (AP-1) binding to DNA. Vb was an effective inhibitor of T/I-stimulated chemokine synthesis, and it accelerated scratch wound healing in vitro. Anti-inflammatory and wound healing activities of Vb were confirmed in vivo in the full-thickness excision wound. Although Pd and Rv did not affect EGFR activation/translocation, they and Qr synergized with TGF-α and T/I in the induction of IL-8 transcription/synthesis while opposing enhanced MCP-1 and IP-10 transcription/synthesis connected with pharmacologically impaired EGFR functioning.

INNOVATION

PPs perturb the EGFR system in human keratinocytes, and this effect may be implicated in the regulation of inflammatory and repair-related processes in the skin.

CONCLUSION

Anti-inflammatory and wound healing effects of PPs depend on their interaction with EGFR-controlled cytoplasmic and nuclear pathways rather than on their direct redox properties.

Plant polyphenols differentially modulate inflammatory responses of human keratinocytes by interfering with activation of transcription factors NFκB and AhR and EGFR-ERK pathway

Molecular mechanisms underlying modulation of inflammatory responses in primary human keratinocytes by plant polyphenols (PPs), namely the glycosylated phenylpropanoid verbascoside, the stilbenoid resveratrol and its glycoside polydatin, and the flavonoid quercetin and its glycoside rutin were evaluated. As non-lethal stimuli, the prototypic ligand for epidermal growth factor receptor (EGFR) transforming growth factor alpha (TGFalpha), the combination of tumor necrosis factor (TNFalpha) and interferon (IFNgamma) (T/I), UVA+UVB irradiation, and bacterial lipopolysaccharide (LPS) were used. We demonstrated differential modulation of inflammatory responses in keratinocytes at signal transduction, gene transcription, and protein synthesis levels as a function of PP chemical structure, the pro-inflammatory trigger used, and PP interaction with intracellular detoxifying systems. The PPs remarkably inhibited constitutive, LPS- and T/I-induced but not TGFalpha-induced ERK phosphorylation. They also suppressed NFkappaB activation by LPS and T/I. Verbascoside and quercetin invariably impaired EGFR phosphorylation and UV-associated aryl hydrocarbon receptor (AhR)-mediated signaling, while rutin, polydatin and resveratrol did not affect EGFR phosphorylation and further activated AhR machinery in UV-exposed keratinocytes. In general, PPs down-regulated gene expression of pro-inflammatory cytokines/enzymes, except significant up-regulation of IL-8 observed under stimulation with TGFalpha. Both spontaneous and T/I-induced release of IL-8 and IP-10 was suppressed, although 50μM resveratrol and polydatin up-regulated IL-8. At this concentration, resveratrol activated both gene expression and de novo synthesis of IL-8 and AhR-mediated mechanisms were involved. We conclude that PPs differentially modulate the inflammatory response of human keratinocytes through distinct signal transduction pathways, including AhR and EGFR.

Differential modulation of stress-inflammation responses by plant polyphenols in cultured normal human keratinocytes and immortalized HaCaT cells

BACKGROUND

Environmental and endogenous stresses to skin are considered causative reasons for skin cancers, premature ageing, and chronic inflammation. Screening of substances with preventive and/or curative properties is currently based on mechanistic studies of their effects towards stress-induced responses in skin cell cultures.

OBJECTIVE

We compared effects of plant polyphenols (PPs) on the constitutive, UVA-, LPS-, or TNF-alpha-induced inflammatory responses in cultured normal human epidermal keratinocytes (NHEK) and immortalized HaCaT cells.

METHODS

Representatives of three classes of PPs, flavonoids, stilbenoids, and phenylpropanoids were studied. Their effects on mRNA were determined by qRT-PCR; protein expression was assayed by Western blot and bioplexed ELISA; phosphorylation of Akt1, ERK1/2, EGFR, and NFkappaB was quantified by intracellular ELISA or Western blot.

RESULTS

PPs or their combination with UVA or LPS induced strong up-regulation of stress responses in HaCaT but not in NHEK. In addition, compared to NHEK, HaCaT responded to TNF-alpha with higher synthesis of MCP-1, IP-10 and IL-8, concomitant with stronger NFkappaB activation. PPs down-regulated the chemokine release from both cell types, although with distinct effects on NFkappaB, Akt1, ERK, and EGFR activation.

CONCLUSION

Results of pharmacological screenings obtained by using HaCaT should be cautiously considered while extending them to primary keratinocytes from human epidermis.

Acteoside inhibits PMA-induced matrix metalloproteinase-9 expression via CaMK/ERK- and JNK/NF-κB-dependent signaling

SCOPE

Acteoside, an active phenylethanoid glycoside found in bitter tea and many medicinal plants, displays chemopreventive properties. The aim of our study was to determine the effect of acteoside on tumor invasion and migration; the possible mechanisms involved in this inhibition were investigated in human fibrosarcoma HT-1080 cells.

METHODS AND RESULTS

We employed invasion, migration and gelatin zymography assays to characterize the effect of acteoside on HT-1080 cells. Transient transfection assays were performed to investigate gene promoter activities, and immunoblot analysis to study its molecular mechanisms of action. We found that acteoside suppresses phorbol-12-myristate-13-acetate (PMA)-enhanced matrix metalloproteinase-9 (MMP-9) expression at the protein, mRNA, and transcriptional levels through the suppression of NF-κB activation. In addition, acteoside repressed the PMA-induced phosphorylation of ERK1/2 (ERK, extracellular regulated kinase) and JNK1/2. Further, we found that acteoside decreased the PMA-induced influx of Ca(2+) and repressed PMA-induced calmodulin-dependent protein kinase (CaMK) phosphorylation. Furthermore, treatment with BAPTA/AM, W7, or capsazepine markedly decreased PMA-induced MMP-9 secretion and cell migration, as well as ERK and JNK/NF-κB activation.

CONCLUSION

Acteoside inhibited PMA-induced invasion and migration of human fibrosarcoma cells via Ca(2+) -dependent CaMK/ERK and JNK/NF-κB-signaling pathways. Acteoside therefore has the potential to be a potent anticancer agent in therapeutic strategies for fibrosarcoma metastasis.