Effect of Artocarpus communis Extract on UVB Irradiation-Induced Oxidative Stress and Inflammation in Hairless Mice

Antioxidant, Anti-Inflammation and Antiaging Activities of Artocarpus altilis Methanolic Extract on Urban Particulate Matter-Induced HaCaT Keratinocytes Damage

Particulate matter (PM) is one of the reasons that exacerbate skin diseases. Impaired barrier function is a common symptom in skin diseases, including atopic dermatitis, eczema and psoriasis. Herbal extracts rich in antioxidants are thought to provide excellent pharmacological activities; however, the anti-pollution activity of Artocarpus altilis extract (AAM) has not been investigated yet. The present study demonstrated that 5 μg/mL of AAM was considered to be a safe dose for further experiments without cytotoxicity. Next, we evaluated the anti-pollution activity of AAM through the PM-induced keratinocytes damage cell model. The results showed that AAM could reduce PM-induced overproduction of intracellular ROS and the final product of lipid peroxidation, 4-hydroxynonenal (4HNE). In addition, AAM not only reduced the inflammatory protein expressions, including tumor necrosis factor α (TNFα), TNF receptor 1 (TNFR1) and cyclooxygenase-2 (COX-2), but also balanced the aging protein ratio of matrix metalloproteinase (MMPs) and tissue inhibitors of metalloproteases (TIMPs) through downregulating the phosphorylation of mitogen-activated protein kinase (MAPK) signaling. For skin barrier protection, AAM could repair PM-induced barrier function proteins damage, including filaggrin, loricrin and aquaporin 3 for providing anti-aging bioactivity. In conclusion, AAM has the potential to be developed as an anti-pollution active ingredient for topical skin products to prevent skin oxidation, inflammation and aging, and restore the skin barrier function.

Photoprotective Potential of the Natural Artocarpin against In Vitro UVB-Induced Apoptosis

Apoptosis, a well-known pattern of programmed cell death, occurs in multicellular organisms not only for controlling tissue homeostasis but also for getting rid of severely damaged cells in order to protect the redundant growth of abnormal cells undergoing cancerous cells. The epidermis of the human skin, composed largely of keratinocytes (KCs), is renewed continuously. Therefore, KCs apoptosis plays a critical role in the maintenance of epidermis structure and function. However, regulated cell death can be disturbed by environmental factors especially ultraviolet radiation (UV) B, leading to the formation of sunburn cells (KCs undergoing UVB-induced apoptosis) and impairing the skin integrity. In the present study, we firstly reported the potential of the natural artocarpin (NAR) to regulate UVB-induced human KCs apoptosis. The NAR showed antilipid peroxidation with an IC₅₀ value of 18.2 ± 1.6 μg/mL, according to TBARS assay while the IC₅₀ value of trolox, a well-known antioxidant, was 7.3 ± 0.8 μg/mL. For cell-based studies, KCs were pretreated with 3.1 μg/mL of the NAR for 24 hr and then exposed to UVB at 55 mJ/cm². Our data indicated that the NAR pretreatment reduces UVB-induced oxidative stress by scavenging free radicals and nitric oxide and therefore prevents reactive oxygen species (ROS) and reactive nitrogen species- (RNS-) mediated apoptosis. The NAR pretreatment has been shown also to reduce the UVB-induced cyclobutane pyrimidine dimer (CPD) lesions by absorbing UVB radiation and regulating the cell cycle phase. Additionally, the NAR pretreatment was found to modulate the expression of cleaved caspases-3 and 8 that trigger different signalling cascades leading to apoptosis. Thus, these results provide a basis for the investigation of the photoprotective effect of the NAR isolated from A. altilis heartwood and suggest that it can be potentially used as an agent against UVB-induced skin damages.

Discovery of new depigmenting compounds and their efficacy to treat hyperpigmentation: Evidence from in vitro study

Human skin pigmentation is a result of constitutive and facultative pigmentation. Facultative pigmentation is frequently stimulated by UV radiation, pharmacologic drugs, and hormones whereby leads to the development of abnormal skin hyperpigmentation. To date, many state-of-art depigmenting compounds have been studied using in vitro model to treat hyperpigmentation problems for cosmetic dermatological applications; little attention has been made to compare the effectiveness of these depigmenting compounds and their mode of actions. In this present article, new and recent depigmenting compounds, their melanogenic pathway targets, and modes of action are reviewed. This article compares the effectiveness of these new depigmenting compounds to modulate several melanogenesis-regulatory enzymes and proteins such as tyrosinase (TYR), TYR-related protein-1 (TRP1), TYR-related protein-2 (TRP2), microphthalmia-associated transcription factor (MITF), extracellular signal-regulated kinase (ERK) and N-terminal kinases (JNK) and mitogen-activated protein kinase p38 (p38 MAPK). Other evidences from in vitro assays such as inhibition on melanosomal transfer, proteasomes, nitric oxide, and inflammation-induced melanogenesis are also highlighted. This article also reviews analytical techniques in different assays performed using in vitro model as well as their advantages and limitations. This article also provides an insight on recent finding and re-examination of some protocols as well as their effectiveness and reliability in the evaluation of depigmenting compounds. Evidence and support from related patents are also incorporated in this present article to give an overview on current patented technology, latest trends, and intellectual values of some depigmenting compounds and protocols, which are rarely highlighted in the literatures.

An Investigation of Potential Sources of Nutraceuticals from the Niger Delta Areas, Nigeria for Attenuating Oxidative Stress

Background: Diets rich in fruits, vegetables, and medicinal plants possess antioxidants potentially capable of mitigating cellular oxidative stress. This study investigated the antioxidant, anti-acetylcholinesterase (AChE), and total phenolic and flavonoids contents (TPC/TFC) of dietary sources traditionally used for memory enhancing in Niger Delta, Nigeria. Methods:Dacroydes edulis methanolic seed extract (DEMSE), Cola lepidota methanolic seed extract (CLMSE), Terminalia catappa methanolic seed extract (TeCMSE), Tricosanthes cucumerina methanolic seed extract (TrCMSE), Tetrapleura tetraptera methanolic seed extract (TTMSE), and defatted Moringa oleifera methanolic seed extract (DMOMSE); Dennettia tripetala methanolic fruit extract (DTMFE), Artocarpus communis methanolic fruit extract (ACMFE), Gnetum africana methanolic leaf extract (GAMLE), Musa paradisiaca methanolic stembark extract (MPMSE), and Mangifera indica methanolic stembark extract (MIMSE) were evaluated for free radical scavenging antioxidant ability using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), reducing power capacity (reduction of ferric iron to ferrous iron), AChE inhibitory potential by Ellman assay, and then TPC/TFC contents determined by estimating milli-equivalents of Gallic acid and Quercetin per gram, respectively. Results: The radical scavenging percentages were as follows: MIMSE (58%), MPMSE (50%), TrCMSE (42%), GAMLE (40%), CLMSE (40%), DMOMSE (38%), and DEMFE (37%) relative to β-tocopherol (98%). The highest iron reducing (antioxidant) capacity was by TrCMSE (52%), MIMSE (40%) and GAMLE (38%). Extracts of MIMSE, TrCMSE, DTMFE, TTMSE, and CLMSE exhibited concentration-dependent AChE inhibitory activity (p < 0.05–0.001). At a concentration of 200 µg/mL, the AChE inhibitory activity and IC₅₀ (µg/mL) exhibited by the most potent extracts were: MIMSE (≈50%/111.9), TrCMSE (≈47%/201.2), DTMFE (≈32%/529.9), TTMSE (≈26%/495.4), and CLMSE (≈25%/438.4). The highest TPC were from MIMSE (156.2), TrCMSE (132.65), GAMLE (123.26), and CLMSE (119.63) in mg gallic acid equivalents/g, and for TFC were: MISME (87.35), GAMLE (73.26), ACMFE (69.54), CLMSE (68.35), and TCMSE2 (64.34) mg quercetin equivalents/gram. Conclusions: The results suggest that certain inedible and edible foodstuffs, most notably MIMSE, MPMSE, TrCMSE, GAMLE, and CLMSE may be beneficial to ameliorate the potentially damaging effects of redox stress.

Total phenylethanoid glycosides and magnoloside IafromMagnolia officinalisvar.bilobafruits inhibit ultraviolet B-induced phototoxicity and inflammation through MAPK/NF-κB signaling pathways

Magnolia officinalisvar.bilobais used as a traditional medicine in China and as a food additive in the United Kingdom and the European Union.

Ginsenoside Rg1 attenuates ultraviolet B-induced glucocortisides resistance in keratinocytes via Nrf2/HDAC2 signalling

Oxidative stress, which occurs after ultraviolet (UV) radiation, usually results in Glucocorticoid (GC) resistance and the subsequent development of skin inflammation. One approach to protecting the skin against UV radiation is the use of antioxidants. The ginsenoside Rg1 is a novel natural antioxidant isolated from the medicinal plant Panax ginseng C.A. Mey. We demonstrated that UVB exposure exacerbated inflammation and reduced both the level of the glucocorticoid receptor (GR) and the efficacy of dexamethasone (Dex) in human keratinocytes (HaCaT cells). Pretreatment with Rg1 increased the expression of GR and restored Dex responsiveness to inflammation in UVB-irradiated HaCaT cells. Mechanistically, Rg1 rescued UVB-induced HDAC2 degradation. HDAC2 knockdown partially abolished the Rg1-induced up-regulation of GR and the enhancement of GC sensitivity. In addition, Rg1 reduced the production of reactive oxygen species (ROS), which preceded the up-regulation of HDAC2, and consequent sensitization of cells to Dex. Moreover, Rg1 treatment promoted the translocation and activation of Nrf2. Nrf2 knockdown partially abolished the Rg1-induced decrease of ROS production and increase of HDAC2. Rg1 also potentiated the anti-inflammatory effects of Dex in UVB-irradiated mouse skin. In conclusion, we demonstrated that Rg1 attenuated UVB-induced GC insensitivity. Notably, these effects were partially mediated by the Nrf2/HDAC2 pathway.

Evaluation of in vitro anti-inflammatory effects of crude ginger and rosemary extracts obtained through supercritical CO2 extraction on macrophage and tumor cell line: the influence of vehicle type

BACKGROUND

Numerous plants from have been investigated due to their anti-inflammatory activity and, among then, extracts or components of ginger (Zingiber officinale Roscoe) and rosemary (Rosmarinus officinalis L.), sources of polyphenolic compounds. 6-gingerol from ginger rhizome and carnosic acid and carnosol from rosemary leaves present anti-tumor, anti-inflammatory and antioxidant activities. However, the evaluation of the mechanisms of action of these and other plant extracts is limited due to their high hydrophobicity. Dimethylsulfoxide (DMSO) is commonly used as a vehicle of liposoluble materials to mammalian cells in vitro, presenting enhanced cell penetration. Liposomes are also able to efficiently deliver agents to mammalian cells, being capable to incorporate in their structure not only hydrophobic molecules, but also hydrophilic and amphiphilic compounds. Another strategy is based on the use of Pluronic F-68, a biocompatible low-foaming, non-ionic surfactant, to disperse hydrophobic components. Here, these three delivery approaches were compared to analyze their influence on the in vitro anti-inflammatory effects of ginger and rosemary extracts, at different concentrations, on primary mammalian cells and on a tumor cell line.

METHODS

Ginger and rosemary extracts free of organic solvents were obtained by supercritical fluid extraction and dispersed in DMSO, Pluronic F-68 or liposomes, in variable concentrations. Cell viability, production of inflammatory mediators and nitric oxide (NO) release were measured in vitro on J774 cell line and murine macrophages primary culture stimulated with bacterial lipopolysaccharide and interferon-γ after being exposed or not to these extracts.

RESULTS

Ginger and rosemary extracts obtained by supercritical CO2 extraction inhibited the production of pro-inflammatory cytokines and the release of NO by peritoneal macrophages and J774 cells. The delivery vehicles influenced the anti-inflammatory effects. Comparatively, the ginger extract showed the highest anti-inflammatory activity on the tumor cell line. Controversially, rosemary extract dispersed on DMSO induced a more significant IL-1 and TNF-α reduction than ginger extract in primary macrophages.

CONCLUSIONS

Amongst the tested delivery vehicles, DMSO was the most suitable, presenting reduced cytotoxicity, followed by Pluronic F-68 and liposomes, provably due to differences in their form of absorption, distribution and cellular metabolism. Co-administration of liposomes and plant extracts may cause death of macrophages cells and induction of NO production. It can be concluded that some of the beneficial effects attributed to extracts of ginger and rosemary may be associated with the inhibition of inflammatory mediators due to their high antioxidant activity. However, these effects were influenced by the type of delivery vehicle.

Isorhamnetin Protects Human Keratinocytes against Ultraviolet B-Induced Cell Damage

Isorhamnetin (3-methylquercetin) is a flavonoid derived from the fruits of certain medicinal plants. This study investigated the photoprotective properties of isorhamnetin against cell damage and apoptosis resulting from excessive ultraviolet (UV) B exposure in human HaCaT keratinocytes. Isorhamnetin eliminated UVB-induced intracellular reactive oxygen species (ROS) and attenuated the oxidative modification of DNA, lipids, and proteins in response to UVB radiation. Moreover, isorhamnetin repressed UVB-facilitated programmed cell death in the keratinocytes, as evidenced by a reduction in apoptotic body formation, and nuclear fragmentation. Additionally, isorhamnetin suppressed the ability of UVB light to trigger mitochondrial dysfunction. Taken together, these results indicate that isorhamnetin has the potential to protect human keratinocytes against UVB-induced cell damage and death.

Blackberry extract inhibits UVB-induced oxidative damage and inflammation through MAP kinases and NF-κB signaling pathways in SKH-1 mice skin

Extensive exposure of solar ultraviolet-B (UVB) radiation to skin induces oxidative stress and inflammation that play a crucial role in the induction of skin cancer. Photochemoprevention with natural products represents a simple but very effective strategy for the management of cutaneous neoplasia. In this study, we investigated whether blackberry extract (BBE) reduces chronic inflammatory responses induced by UVB irradiation in SKH-1 hairless mice skin. Mice were exposed to UVB radiation (100 mJ/cm(2)) on alternate days for 10 weeks, and BBE (10% and 20%) was applied topically a day before UVB exposure. Our results show that BBE suppressed UVB-induced hyperplasia and reduced infiltration of inflammatory cells in the SKH-1 hairless mice skin. BBE treatment reduced glutathione (GSH) depletion, lipid peroxidation (LPO), and myeloperoxidase (MPO) in mouse skin by chronic UVB exposure. BBE significantly decreased the level of pro-inflammatory cytokines IL-6 and TNF-α in UVB-exposed skin. Likewise, UVB-induced inflammatory responses were diminished by BBE as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, BBE also reduced inflammatory mediators such as cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and inducible nitric oxide synthase (iNOS) levels in UVB-exposed skin. Treatment with BBE inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mouse skin. Immunohistochemistry analysis revealed that topical application of BBE inhibited the expression of 8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodG), cyclobutane pyrimidine dimers (CPD), proliferating cell nuclear antigen (PCNA), and cyclin D1 in UVB-exposed skin. Collectively, these data indicate that BBE protects from UVB-induced oxidative damage and inflammation by modulating MAP kinase and NF-κB signaling pathways.

P38 and JNK signal pathways are involved in the regulation of phlorizin against UVB-induced skin damage

Phlorizin is well known to inhibit sodium/glucose cotransporters in the kidney and intestine for the treatment of diabetes, obesity and stress hyperglycaemia. However, the effects of phlorizin against ultraviolet B (UVB) irradiation and its molecular mechanism are still unknown. We examined the effects of phlorizin on skin keratinocyte apoptosis, reactive oxygen species (ROS) production, pro-inflammatory responses after UVB irradiation and the changes of some signal molecules by in vitro and in vivo assay. We observed that phlorizin pretreatments inhibited HaCaT cell apoptosis and overproduction of ROS induced by UVB. Phlorizin also decreased the expression of UVB-induced pro-inflammatory cytokines, such as interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and interleukin-8 (IL-8) at the mRNA level. Topical application of phlorizin on UVB-exposed skin of nude mice prevented the formation of scaly skin and erythema, inhibited the increase of epidermal thickness and reduced acute inflammation infiltration in skin. Additionally, PCR, Western blot and immunohistochemical data showed that phlorizin reversed the overexpression of cyclooxygenase-2 (Cox-2) induced by UVB irradiation both in vitro and in vivo. The activation of p38 and JNK mitogen-activated protein kinases (MAPK) after UVB irradiation was also inhibited by phlorizin. These findings suggest that phlorizin is effective in protecting skin against UVB-induced skin damage by decreasing ROS overproduction, Cox-2 expression and the subsequent excessive inflammation reactions. It seemed that p38 and JNK MAPK signal pathways are involved in the regulation of the protective function of phlorizin.

Photo-protective effect of americanin B against ultraviolet B-induced damage in cultured human keratinocytes

Excessive ultraviolet (UV) radiation, a constituent of sunlight, can induce multiple types of skin damage. We recently demonstrated that americanin B, a lignin compound, protected cells against hydrogen peroxide (H2O2)-induced damage by exerting antioxidant effects and inhibiting apoptosis. In this study, we investigated the ability of americanin B to protect against cell injury induced by UVB (280-320nm), the most harmful UV wavelengths, in human HaCaT keratinocytes. Americanin B absorbed UVB, eliminated UVB-induced intracellular reactive oxygen species (ROS), and decreased the extent of UVB-induced oxidative modification of lipids, proteins, and DNA. In addition, americanin B inhibited UVB-induced apoptosis, as indicated by reductions in apoptotic body formation and DNA fragmentation. Furthermore, americanin B reversed the depolarization of the mitochondrial membrane induced by UVB exposure. These protective activities were associated with down-regulation of apoptosis-promoting proteins, Bax, caspase-9, and caspase-3 and up-regulation of an apoptosis inhibitor, Bcl-2. These results suggest that americanin B can protect human keratinocytes against UVB-induced cell damage.

Cyanidin-3-glucoside inhibits UVB-induced oxidative damage and inflammation by regulating MAP kinase and NF-κB signaling pathways in SKH-1 hairless mice skin

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE2 and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2'-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways.