Kushenol C from Sophora flavescens protects against UVB-induced skin damage in mice through suppression of inflammation and oxidative stress.

Sophora flavescens has been used in traditional medicine for the treatment of various diseases such as viral hepatitis, fever, cancer, and pain. It is known to contain many bioactive compounds including prenylated flavonoids such as kurarinone, sophoraflavanone G, kuraridine and isoxanthohumol. These flavonoids have been confirmed to have anti-inflammatory, α-glucosidase inhibitory and antioxidant performances. However, the protective activities against UV-induced skin damage of kushenol C from S. flavescens have not yet been elucidated. In this study, we explored the protective effect of kushenol C against the skin damage induced by UVB in mice. Our results showed that kushenol C treatment significantly recovered UVB-induced skin damage, the degradation of collagen, mast cell infiltration, together with epidermal hyperplasia in mice. Furthermore, the treatment of kushenol C remarkably suppressed the generation of pro-inflammatory mediators in the mice irradiated by UVB. More so, treatment with kushenol C suppressed the oxidative stress in mice irradiated by UVB. In conclusion, these results showed that kushenol C from S. flavescens has potentialities to treat skin injury via suppressing skin damage induced by UVB and oxidative stress.

Diospyros lotus leaf extract and its main component myricitrin regulate pruritus through the inhibition of astrocyte activation.

Diospyros lotus is a deciduous plant native to Asian countries, including Korea, Japan and China, and southeast Europe. In traditional medicine, Diospyros lotus is used as an anticancer, antidiabetic and antipyretic agent. The present study aimed to evaluate the effect of Diospyros lotus leaf extract (DLE) in ameliorating histamine-independent pruritus. Activation of signal transducer and activator of transcription 3 (STAT3) in astrocytes contributes to pruritus. In this study, the effects of DLE and its main component, myricetin (MC), on the activation of STAT3, expression of glial fibrillary acidic protein (GFAP), and production of lipocalin-2 (LCN2) in IL-6-treated astrocytes and chloroquine-injected mice were investigated through western blot, reverse transcription-quantitative PCR, and immunofluorescence staining. DLE and MC inhibited STAT3 activation, GFAP expression and LCN2 release via inositol 1,4,5-trisphosphate receptor type 1 blockade in astrocytes. DLE and MC ameliorated scratching behavior, expression of GFAP, mast cell infiltration and serum IL-6 levels in chloroquine-injected mice. These results suggested that DLE and MC can be used as oral therapeutic agents for the treatment and management of pruritus.

Citric acid and enzyme-assisted modification of flavonoids from celery (Apium graveolens) extract and their anti-inflammatory activity in HMC-1.2 cells.

Apium graveolens (celery) of the family Apiaceae contains bioactive compounds including luteolin and apigenin. The purpose of this study was to increase the extraction yield of apigenin and luteolin in celery extract using green technology and to evaluate their biological activities. The results showed that CA and ß-glucosidase-assisted celery extraction transformed apiin in the celery to apigenin with an increase in luteolin concentration. The CA and ß-glucosidase-treated celery extract (CAGE) improved the anti-inflammatory properties of celery extract by inhibiting the expression and production of inflammatory cytokines (IL-6, IL-8, IL-31, and TNF-α) in IL-33-stimulated mast cells (HMC-1.2 cells). Their mechanism of action was tied to the inhibition of ERK, JNK, IKKα, IκBα, and NF-κB activation by CAGE in the stimulated cells. In conclusion, CA and enzyme treatment can be considered as a useful biotechnology tool for the improvement of bioactive compounds in celery and hence improve on their bioactivity. PRACTICAL APPLICATIONS: Apium graveolens commonly called celery is an edible agricultural product cultivated throughout the world and known as a "superfood." Celery contains bioactive compounds including apigenin and luteolin that contribute to their described biological activities. However, extracting celery using normal extraction procedures such as hot water and ethanol methods yields only a small amount of apigenin and luteolin. In the present study, we introduced an eco-friendly method using citric and ß-glucosidase to obtain apigenin and luteolin-rich celery extract with improved anti-inflammatory activities. The present work will spark studies on the conversion of less biologically active compounds in functional food materials to more active compounds using CA and ß-glucosidase, and the development of functional food with specifically enriched bioactive substances at the industrial levels.

Anti­inflammatory effect of Chrysanthemum zawadskii, peppermint, Glycyrrhiza glabra herbal mixture in lipopolysaccharide­stimulated RAW264.7 macrophages.

The normal inflammatory reaction protects the body from harmful external factors, whereas abnormal chronic inflammation can cause various diseases, including cancer. The purpose of the present study was to investigate the anti­inflammatory activity of a mixture of Chrysanthemum zawadskii, peppermint and Glycyrrhiza glabra (CPG) by analyzing the expression levels of inflammatory mediators, cytokines and transcription factors in lipopolysaccharide (LPS)­stimulated Raw264.7 cells. A nitric oxide assay, ELISA, western blotting and immunofluorescence staining were performed to investigate the anti­inflammatory activity of the CPG mixture. Pretreatment of Raw264.7 cells with CPG inhibited the increase of inflammatory mediators (inducible nitric oxide synthase, cyclooxygenase­2 and IFN­ß) induced by LPS. Additionally, it inhibited the production of pro­inflammatory cytokines (TNF­α, IL­6 and IL­1ß). CPG suppressed LPS­induced phosphorylation of STAT1, AKT, Iκb and NF­κB. Furthermore, CPG inhibited the translocation of NF­κB into the nucleus. In summary, CPG could inhibit LPS­induced inflammation, which occurs primarily through the AKT/Iκb/NF­κB signaling pathway in RAW264.7 cells.

Protective effects of halophyte complex extract against UVB-induced damage in human keratinocytes and the skin of hairless mice.

Limonium tetragonum, Triglochin maritimum, Artemisia scoparia and red ginseng have been used as folk remedies for treating a variety of diseases. In the current study, the protective effects of halophyte and red ginseng against ultraviolet (UV)-induced skin damage were investigated. Halophyte red ginseng complex extract (HRCE) was prepared and its effects on UV-B irradiated human keratinocytes and mouse skin were studied through ELISA, Western blotting immunofluorescence and histological staining. HRCE inhibited peroxide-induced damage in human keratinocytes. HRCE also inhibited UVB-induced collagen and elastin degradation in human keratinocytes and mouse skin. In addition, HRCE inhibited mast cell infiltration in the skin of mice irradiated with UVB light. This effect was likely due to HRCE inhibiting the activation of MAPK and NF-κB. By protecting the skin from UVB-induced skin damage, HRCE has the potential to be used in the treatment and prevention of UV-induced skin damage and photoaging.

Kushenol C Prevents Tert-Butyl Hydroperoxide and Acetaminophen-Induced Liver Injury.

Sophora flavescens, also known as Kushen, has traditionally been used as a herbal medicine. In the present study we evaluated the ameliorative effects of kushenol C (KC) from S. flavescens against tBHP (tert-Butyl hydroperoxide)-induced oxidative stress in hepatocellular carcinoma (HEPG2) cells and acetaminophen (APAP)-induced hepatotoxicity in mice. KC pretreatment protected the HEPG2 cells against oxidative stress by reducing cell death, apoptosis and reactive oxygen species (ROS) generation. KC pretreatment also upregulated pro-caspase 3 and GSH (glutathione) as well as expression of 8-Oxoguanine DNA Glycosylase (OGG1) in the HEPG2 cells. The mechanism of action was partly related by KC's activation of Akt (Protein kinase B (PKB)) and Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) in the HepG2 cells. In in vivo investigations, coadministration of mice with KC and APAP significantly attenuated APAP-induced hepatotoxicity and liver damage, as the serum enzymatic activity of aspartate aminotransferase and alanine aminotransferase, as well as liver lipid peroxidation and cleaved caspase 3 expression, were reduced in APAP-treated mice. Coadministration with KC also up-regulated antioxidant enzyme expression and prevented the production of proinflammatory mediators in APAP-treated mice. Taken together, these results showed that KC treatment has potential as a therapeutic agent against liver injury through the suppression of oxidative stress.

In vitro Anti-Inflammatory and Anti-Oxidative Stress Activities of Kushenol C Isolated from the Roots of Sophora flavescens.

Kushenol C (KC) is a prenylated flavonoid isolated from the roots of Sophora flavescens aiton. Little is known about its anti-inflammatory and anti-oxidative stress activities. Here, we investigated the anti-inflammatory and anti-oxidative stress effects of KC in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages, and tert-butyl hydroperoxide (tBHP)-induced oxidative stress in HaCaT cells. The results demonstrated that KC dose-dependently suppressed the production of inflammatory mediators, including NO, PGE2, IL-6, IL1ß, MCP-1, and IFN-ß in LPS-stimulated RAW264.7 macrophages. The study demonstrated that the inhibition of STAT1, STAT6, and NF-κB activations by KC might have been responsible for the inhibition of NO, PGE2, IL-6, IL1ß, MCP-1, and IFN-ß in the LPS-stimulated RAW264.7 macrophages. KC also upregulated the expression of HO-1 and its activities in the LPS-stimulated RAW264.7 macrophages. The upregulation of Nrf2 transcription activities by KC in the LPS-stimulated RAW264.7 macrophages was demonstrated to be responsible for the upregulation of HO-1 expression and its activity in LPS-stimulated RAW264.7 macrophages. In HaCaT cells, KC prevented DNA damage and cell death by upregulating the endogenous antioxidant defense system involving glutathione, superoxide dismutase, and catalase, which prevented reactive oxygen species production from tert-butyl hydroperoxide (tBHP)-induced oxidative stress in HaCaT cells. The upregulated activation of Nrf2 and Akt in the PI3K-Akt signaling pathway by KC was demonstrated to be responsible for the anti-oxidative stress activity of KC in HaCaT cells. Collectively, the study suggests that KC can be further investigated as a potential anti-inflammatory candidate for the treatment of inflammatory diseases.

Anti-atopic dermatitis effects of hydrolyzed celery extract in mice.

This study investigated the ameliorative effects of acid hydrolyzed celery extract (HCE) and celery extract (CE) in an atopic dermatitis (AD) mice model. The results of the study showed that HCE, more than CE improved AD-like skin lesions caused by fluoro-2,4-dinitrobenzene and house dust mite antigen administration. Further analysis also showed the dominance of HCE than CE in preventing mast cell infiltration in the dermis; inhibiting the IL-31 expression in mice skin and reducing the immunoglobulin-E, IL-4, IL-5, TNF-α, IFN-γ, IL-31, and TSLP in serum of mice. Using in vitro studies in a murine macrophage cell line, we showed that apigetrin, luteolin, and apigenin present in both extracts could be accountable for the observed effects as these three compounds and not apiin prevented the nitric oxide production in the murine macrophage. Based on this study, we suggest that hydrolyzing celery extracts can improve the therapeutic efficacy of celery extracts for management of AD. PRACTICAL APPLICATIONS: Apigenin, apigetrin, and luteolin are known biologically active compounds present in celery. Acid hydrolysis could increase the biologically active compounds in natural products. The research investigated the effects of acid HCE in a mice model of atopic dermatitis. The data obtained from this study sheds light on the use of hydrolysis methods to improve the biological activities of plant extracts used in nutraceutical industries.

Luteolin suppresses IL-31 production in IL-33-stimulated mast cells through MAPK and NF-κB signaling pathways.

IL-31 and IL-33 are cytokines, which are expressed in many inflammatory and pathological disorders, thus suggesting an IL-31/IL-33 axis interaction in pathological diseases. Luteolin from natural products is known for its anti-inflammatory activities associated with the regulation of inflammatory signaling pathways. Here, we investigated the effects of luteolin in the regulation of IL-33-stimulated production and secretion of IL-31 in HMC-1.2 mast cells. Human mast cells (HMC-1.2) were treated with luteolin and stimulated with IL-33. Real-time PCR was used to measure IL-31 mRNA expression. Western blot and immunofluorescence assays were used to measure IL-31 expression. ELISA techniques were used to measure IL-31 secretion and NF-κB-DNA-binding activities. The results revealed that luteolin inhibited the expression of IL-31 in IL-33-stimulated HMC-1.2 cells at the mRNA and protein levels. Also, Luteolin inhibited the secretion of IL-31 into the cell culture media of the IL-33-stimulated HMC-1.2 cells. Further findings demonstrated that luteolin inhibited the activation of ERK, JNK, p38, and NF-κB p65 in the IL-33-stimulated HMC-1.2 cells. In addition, luteolin also prevented the nuclear translocation and binding of p65 to its DNA-binding site. Based on the results, luteolin may be considered as a potential therapeutic or functional food agent for the prevention and/or treatment of IL-31 and IL-33-related diseases.

Anti-obesity effects of enzyme-treated celery extract in mice fed with high-fat diet.

The present study demonstrated the anti-obesity effects of enzyme-treated celery extract (ECE) in mice on high-fat diet (HFD). In vitro studies showed that ECE has anti-adipogenic properties by inhibiting lipid accumulations in adipose cells. In vivo studies indicated that the administration of ECE markedly prevented HFD-induced body weight gain, food efficiency ratio, and epididymal fat and liver weights. ECE reduced lipid parameters, cardiac risk factor, and atherogenic index in obese mice. ECE prevented a diabetes state by improving adipokines levels, reducing glucose levels, and preventing insulin resistance. Moreover, ECE prevented HFD-induced liver damage by preventing hepatic steatosis and upregulation of liver antioxidant enzymes. The mechanism of ECE was partially investigated to involve the activation of 5' adenosine monophosphate-activated protein kinase and hence the downregulation of CCAAT/enhancer binding protein α and peroxisome proliferator-activated receptor γ by ECE. Our results suggest that ECE could be used as functional food materials for the prevention of obesity. PRACTICAL APPLICATIONS: Apium graveolens is a popular plant with nutritive and medicinal benefits. It contains bioactive compounds such as apiin, apigenin, and luteolin. However, these compounds are rendered insoluble due to their interaction with polysaccharides in the cell wall thus making them less bioavailable. Hydrolyzing them could increase the yield of bioactive compounds in celery. This pilot study demonstrates that pectinase-treated celery extract has anti-obesity effects. The results of this research demonstrate the use of enzymes in improving the biological activities of plant extracts and suggest the use of enzyme-assisted extraction techniques in the industrial production of health functional food from celery.

Anti-inflammatory effect of hydrolyzed celery leaves extract in murine primary splenocyte.

Apium graveolens (celery) has been used in traditional medicine for the treatment of various ailments. However, its molecular mechanism of action in inflammatory response is unclear. In this study, we sought to investigate the anti-inflammatory properties of celery leaves. We prepared an acid-hydrolyzed extract of celery leaves (HCE) and studied its effects on concanavalin A (ConA)-stimulated primary splenocytes. HCE at noncytotoxic concentrations, inhibited ConA-induced proliferation of splenocytes. HCE treatment reduced CD4+ T cell population and decreased expressions and production of cytokines in stimulated splenocytes. In addition, HCE significantly inhibited NO production and reduced the expression of COX-2 mRNA in the stimulated splenocytes. The effects seen were probably due to HCE's downregulation of NF-κB/p65 activation in splenocytes. By providing the anti-inflammatory mechanism of action of HCE, these findings are potentially important for future studies that may, ultimately result in the potential use of celery for the treatment/prevention of inflammatory diseases. PRACTICAL APPLICATIONS: Apium graveolens is a well-known edible plant with high concentrations of bioactive compounds such as apigenin, luteolin, and kaempferol. The research investigated the effects of A. graveolens leaves in splenocyte proliferation, and production of inflammatory mediators and cytokines. The data obtained from this study shed light on the use of plant extracts and plant-based bioactives in nutraceutical industries as potential functional food materials for preventing inflammatory diseases.

Chlorogenic acid-rich Solanum melongena extract has protective potential against rotenone-induced neurotoxicity in PC-12 cells.

Neurodegenerative diseases are major threats to human health. Here, through fluorescence, colorimetric, immunoblotting, spectroscopy, and laser scanning confocal microscopic techniques, we investigated the neuroprotective properties of chlorogenic acid-rich Solanum melongena extracts (SM extract) in rotenone-induced PC-12 cell death. The results showed that rotenone caused apoptosis to PC-12 cells by elevating Bax/Bcl-2 ratio and increasing caspase-3 activity. Rotenone also increased ROS in cells while suppressing SOD and catalase activities. This resulted in the depletion of ATP in cells by blocking mitochondria complex I activity. Pretreatment of the cells with SM extract at concentrations of 100, 250, and 500 µg/ml before incubation for 24 hr with rotenone significantly prevented apoptosis, decreased ROS, and increased ATP production in the cells. SM extract upregulated SOD and catalase activities in the cells. These results unveil evidence that SM extract content neuroprotective properties that can be exploited to prevent and treat neurodegenerative diseases. PRACTICAL APPLICATIONS: Solanum melongena eggplant is a popular ingredient in many traditional recipes and is well known in Asia for its medicinal benefits. Despite numerous scientific reports of the potential health benefits of this plant, reports on its effects in neurodegenerative diseases is still lacking. This pilot study demonstrates that S. melongena eggplant can protect against neurotoxicity in neurodegenerative diseases. The results of this research serves as a base for further research on eggplant that will result in its usage on a larger scale as functional food materials.

Biological activities of water-soluble polysaccharides from Opuntia humifusa stem in high-fat-diet-fed mice.

Water-soluble polysaccharide (WSP) of Opuntia humifusa stems was extracted and its biological activities in mice fed with a high-fat diet (HFD) were investigated. The mice were treated with oral doses of WSP for 4 weeks. Body weight, fat mass, serum lipid, and hormone profiles, gastrointestinal tract changes were evaluated. WSP treatment resulted in a decrease in fat mass and improvement of lipid and hormone profiles associated with HFD consumption. In addition, WSP improved the gastrointestinal health of the mice by increasing ghrelin-releasing cells and serotonin-positive cells and boosted immune functions by increasing the expression of CD4+ cells and nitric oxide synthase. Also, WSP treatment reduced gastrointestinal transit time and increased fecal moisture content. These findings suggest that a sufficient intake of WSP from O. humifusa can be beneficial in preventing disorders that are associated with the consumption of HFD including the preservation of gastrointestinal health. PRACTICAL APPLICATIONS: Opuntia humifusa is a traditional edible plant widely eaten in Asia for its high concentrations of vitamin C, polyphenols, and flavonoids. The research investigated the biological activity of WSP extracted from O. humifusa stems. The data obtained from this study sheds light on the use of plant-based polysaccharides in nutraceutical industries as potential functional food materials for the prevention of HFD-related disorders and improvement of gastrointestinal health. The results of this research could serve as a base for further research on this polysaccharide as a source of functional polysaccharides and promotes its usage on a large scale in functional food materials.

Soybean Fermented with Bacillus amyloliquefaciens (Cheonggukjang) Ameliorates Atopic Dermatitis-Like Skin Lesion in Mice by Suppressing Infiltration of Mast Cells and Production of IL-31 Cytokine.

The present study was conducted with the aim to investigate the ameliorative effects of a new soybean product (cheonggukjang) fermented with Bacillus amyloliquefaciens SCGB1 (SFBA) in atopic dermatitis (AD) mouse model. Visual evaluation of AD induction in the mice indicated the remarkable control of SFBA in reducing the pathological severity of AD-like skin lesions reported as the SCORAD score of AD clinical symptoms. The results revealed that SFBA reduced dorsal skin and epidermal thickness to a similar extent with prednisolone. Further analysis revealed the dominance of SFBA in restraining mast cell infiltration in the dermis; immunoglobulin-E expression in serum; and TH2 IL-4 cytokine and itch-related IL-31 cytokine in the mice skin and serum. SFBA also suppressed scratching behaviours in mice induced by compound 48/80. Further histological findings also revealed the alleviation of collagen fiber deposition in dermal skin of the AD mice model. These actions of SFBA were examined to be mediated by its suppression of the phosphorylation activation of key signalling molecules such as NF-kappaB and MAPK responsible for the induction of cytokine production. Thus, SFBA can be considered as a promising functional food for managing clinical, histological and immunological spectra associated with AD.

Muscat Bailey A grape stalk extract ameliorates high-fat diet­induced obesity by downregulating PPARγ and C/EPBα in mice.

Muscat Bailey A grape stalk is an organic waste produced in marked amounts during the vinification of grapes. Previous studies have indicated that grape stalk is rich in bioactive phenolic compounds, and exhibits antioxidant and UV­protective activities. However, its effects on obesity and obesity­associated disorders have not yet been investigated. The effects of grape stalk extract on improving metabolic features were examined using a high­fat diet (HFD)­induced obesity mouse model. Oral administration of 200 mg/kg/day grape stalk extract over 16 weeks markedly prevented HFD­induced obesity, hepatic steatosis, diabetic symptoms and the risk of developing cardiovascular disease. Furthermore, grape stalk extract prevented oxidative stress and inflammation caused by HFD in mice. The beneficial effect may be associated with CCAAT/enhancer­binding protein α and peroxisome­proliferator­activated receptor Î³ down-regulation in liver tissue. Collectively, the results of the present study indicated that grape stalk extract may be a potent functional food ingredient for preventing obesity, hepatic steatosis and type 2 diabetes.

Anti-obesity effects of Diospyros lotus leaf extract in mice with high-fat diet-induced obesity.

Diospyros (D.) lotus has been demonstrated to have antioxidant and anti­inflammatory properties. The purpose of the present study was to evaluate the effect of D. lotus leaf water extract (DLE) on high­fat diet (HFD)­induced obesity in C57BL/6 mice. The present study first investigated the effect of DLE on the lipid accumulation and triglyceride (TG) contents in 3T3­L1 cells, and the results revealed that treatment with DLE suppressed the lipid accumulation and TG level. Subsequently, the anti­obesity effects of DLE were investigated in vivo. Oral administration of DLE reduced the body weight gain, food efficiency ratio, and liver and visceral fat weight in mice fed with a HFD. DLE administration in these mice also reduced TG, total cholesterol, low­density lipoprotein cholesterol, glucose, insulin and leptin levels, as well as the atherogenic index. Furthermore, DLE administration decreased hepatic steatosis, as well as serum aspartate transaminase, alanine transaminase and alkaline phosphatase levels in mice fed with HFD. It was further observed that treatment of the HFD­fed mice with DLE prevented lipid peroxidation, while it recovered glutathione depletion and the activities of superoxide dismutase, catalase and glutathione peroxidase. In conclusion, the current study suggests that the anti­obesity effect of DLE may provide positive insights as a potential functional food ingredient for the prevention of obesity.

Tyrosinase inhibitory components from the seeds of Cassia tora.

Ten compounds (1-10) isolated from the seeds of Cassia tora were evaluated for tyrosinase inhibition. Compounds 3, 4, and 7 inhibited tyrosinase enzymatic activity in a dose-dependent manner, with IC50 values of 3.0 ± 0.8, 7.0 ± 0.4, and 9.2 ± 3.4 µM, respectively. Kinetic analyses revealed a mechanism consistent with competitive inhibition. In silico molecular docking showed that compounds 3 and 4 docked in the active site of tyrosinase, whereas 7 interacted with Ala246 and Val248 at outside of the active site, and His244 and Glu256 at inside. Additionally, compounds 3, 4, and 7 suppressed melanogenesis in α-MSH-treated B16F10 melanoma cells at a concentration of 10 µM.

Ameliorative effects of fruit stem extract from Muscat Bailey A against chronic UV-induced skin damage in BALB/c mice.

This study analyzed fruit stem extract (MGFE) from Muscat Bailey A grape (Vitis labrusca × Vitis vinifera) for their ameliorative effects on Ultraviolet B (UVB)-induced skin damage in Balb/c mice. Well established in vivo assays were used to determine the biological effects of MGFE upon UVB irradiation of BALB/c mice. The results showed that treatment with MGFE recovered glutathione depletion, prevented lipid peroxidation of tissues and decreased the expression of DNA repair enzyme oxo guanine glycosylase-1. MGFE recovered the skin conditions in UVB-irradiated Balb/c mice. Moreover, MGFE inhibited dermal infiltration of inflammatory cells and reduced serum tumor necrosis factor alpha and interleukin-6 levels. Finally, MGFE treatment inhibited UVB-induced melanin formation and collagen fiber destruction through the inhibition of matrix metalloproteinase-1 expression. Through high-performance liquid chromatography analysis, catechin, epicatechin, and trans-resveratrol were found to be among the main active compounds present in MGFE. Taken together, these results indicated that MGFE has potentials as topical therapeutic materials against skin damage by inhibiting oxidative stress and inflammatory.

Ameliorative effects of Diospyros lotus leaf extract against UVB-induced skin damage in BALB/c mice.

The aim of this study was to investigate the protective effect of Diospyros lotus leaf extract (DLE) on UVB-induced skin damage in mice. UVB irradiation of mice skin incurred significant damage to mice skin; increased thiobarbituric acid-reactive substance level; decreased superoxide dismutase; and glutathione levels in mice skin tissues. More so, UVB irradiation led to collagen degradation and infiltration of mast cell and neutrophils into mice skin leading to inflammation. However, topical application of DLE significantly reversed these conditions with the result comparable to l-ascorbic acid. Myricitrin, gallic acid, astragalin, myricetin-3-O-glactosside, and myricetin through high-performance liquid chromatography analysis were further determined to be the primary active compounds in DLE. In conclusion, our study showed that DLE has potentials as local therapeutic materials against skin damage by inhibiting oxidative stress and UVB-induced skin damage.

Protective effects of grape stem extract against UVB-induced damage in C57BL mice skin.

Humans have become exposed to another form of a trait which is ultraviolet B (UVB) radiation reaching the earth's surface. This has become a major source of oxidative stress that ultimately leads to inflammation, DNA damage, photoaging and pigmentation disorders etc. Although several studies have shown the photo-protective role of different grape parts like the fruits and seeds, little or no data demonstrating the in vivo photo-protective role of grape stem, which is the most discarded part of the grape are available. We evaluated the protective influence of grape stem extract against UVB-induced oxidative damage in C57BL mice characterized by epidermal hyperplasia, pigmentation, collagen degradation and inflammation. Grape stem extract was administered topically 1week before UVB irradiation (120mJ/cm2) and continued until the termination of the experiment. A group of non-irradiated mice and a group of irradiated mice topically administered with propylene were used as a negative and positive control. Epidermal thickness, pigmentation, erythema, mast cell and neutrophil infiltration, collagen degradation and COX-2, Nrf2, and HO-1 expressions were evaluated. Grape stem extract markedly recovered skin damage induced by the UVB radiation through the prevention of epidermal hyperplasia, pigmentation, erythema, mast cell and neutrophil infiltrations, collagen degradation and COX-2, Nrf2, and HO-1 expressions. Our study demonstrated for the first time in C57BL mice that grape stem extract reduces UVB-induced oxidative damage and hence can play a protective role in skin photo-damage.