Inhibition effect of Gynura procumbens extract on UV-B-induced matrix-metalloproteinase expression in human dermal fibroblasts

Therapeutic Effect of Dunaliella salina Microalgae on Thioacetamide- (TAA-) Induced Hepatic Liver Fibrosis in Rats: Role of TGF-β and MMP9

Liver fibrosis represents a serious global health-care problem and is the outcome of many chronic liver diseases, cirrhosis, hepatitis, and toxin accumulation. The present study aimed to evaluate the antifibrotic curative effect of Dunaliella salina (D. salina) on thioacetamide- (TAA-) induced liver fibrosis in rats. Liver fibrosis was induced by TAA (200mg/kg; i.p.) twice per week for 6 weeks. D. salina was given orally (100 and 200 mg/kg) and silymarin was given orally (100 mg/kg) daily, for 4 weeks after TAA. Serum transaminase activities, liver inflammatory cytokines, fibrotic biomarkers, and liver histopathology were assessed. TAA significantly (p<0.05) elevated serum activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and serum levels of total bilirubin, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and transforming growth factor-beta (TGF-β) with a reduction in albumin. In addition, TAA increased hepatic contents of collagen I, a-smooth muscle actin (α-SMA), and tissue inhibitors of metalloproteinase (TIMP-1), reduced matrix metalloproteinase 9 (MMP9), and finally produced marked degeneration and fibrosis of hepatocytes. Treatment with D. salina or silymarin improved the histological feature of hepatocytes and ameliorated the deleterious effects of TAA in a dose-dependent manner. Based on these results, it could be concluded that the use of D. salina could be assigned for liver fibrosis treatment via its anti-inflammatory and antifibrotic properties.

Organogermanium suppresses cell death due to oxidative stress in normal human dermal fibroblasts

Reactive oxygen species (ROS) are very harmful to dermal cells, and it is thus important to develop cosmetics that protect the skin from ROS and other stimuli. Repagermanium is a synthetic water-soluble organogermanium polymer, and in this study, we attempted to visualize the incorporation of germanium into normal human dermal fibroblasts (NHDFs) using isotope microscopy. In addition, the content of 3-(trihydroxygermyl)propanoic acid (THGP), a hydrolyzed monomer of repagermanium, in NHDFs was determined through liquid chromatography mass spectrometry (LC-MS/MS), and the dose-dependent incorporation of THGP was confirmed. We then evaluated the preventive effects of THGP against ROS-induced NHDF death and confirmed the observed preventive effects through gene profiling and expression analysis. The addition of 0.59–5.9 mM THGP reduced cell death resulting from ROS damage caused by the reaction between xanthine oxidase and hypoxanthine and the direct addition of H₂O₂. Furthermore, this study provides the first demonstration that the effect of THGP was not due to the direct scavenging of ROS, which indicates that the mechanism of THGP differs from that of general antioxidants, such as ascorbic acid. The gene profiling and expression analysis showed that THGP suppressed the expression of the nuclear receptor subfamily 4 group A member 2 (NR4A2) gene, which is related to cell death, and the interleukin 6 (IL6) and chemokine (C-X-C motif) ligand 2 (CXCL2) genes, which are related to the inflammatory response. Furthermore, the production of IL6 induced by H₂O₂ was suppressed by the THGP treatment. Our data suggest that the preventive effect of THGP against ROS-induced cell death is not due to antioxidant enzymes or ROS scavenging.

Strategy for rapid screening of antioxidant and anti-inflammatory active ingredients in Gynura procumbens (Lour.) Merr. based on UHPLC-Q-TOF-MS/MS and characteristic ion filtration

Gynura procumbens (Lour.) Merr. is traditionally used as a raw material for making dumplings or steamed stuffed buns, and its fresh leaves are boiled with water for tea. Herein, we established an ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) combined with characteristic ion filtration (CIF) strategy to rapidly screen active ingredients with antioxidant and anti-inflammatory properties in G. procumbens. This strategy involved screening the active part of G. procumbens using antioxidation and anti-inflammatory activity assays; discovering the active compounds by speculating on the active site's chemical composition by UHPLC-Q-TOF-MS/MS plus CIF; and verifying the active compounds' activities. The ethyl acetate extract (EEAF) of G. procumbens was the major active site. Eighty-one compounds were identified from the EEAF using UHPLC-Q-TOF-MS/MS plus CIF. Furthermore, polyphenols such as cynarine, isochlorogenic acids A and isochlorogenic acids C have excellent antioxidizing and anti-inflammatory activities. This study provides a practical strategy for rapid in vitro screening of the antioxidizing and anti-inflammatory activities of traditional vegetables and herbs and identification of active ingredients.

Molecular Mechanisms of Dermal Aging and Antiaging Approaches

The dermis is primarily composed of the extracellular matrix (ECM) and fibroblasts. During the aging process, the dermis undergoes significant changes. Collagen, which is a major component of ECM, becomes fragmented and coarsely distributed, and its total amount decreases. This is mainly due to increased activity of matrix metalloproteinases, and impaired transforming growth factor-β signaling induced by reactive oxygen species generated during aging. The reduction in the amount of collagen hinders the mechanical interaction between fibroblasts and the ECM, and consequently leads to the deterioration of fibroblast function and further decrease in the amount of dermal collagen. Other ECM components, including elastic fibers, glycosaminglycans (GAGs), and proteoglycans (PGs), also change during aging, ultimately leading to a reduction in the amount of functional components. Elastic fibers decrease in intrinsically aged skin, but accumulate abnormally in photoaged skin. The changes in the levels of GAGs and PGs are highly diverse, and previous studies have reported conflicting results. A reduction in the levels of functional dermal components results in the emergence of clinical aging features, such as wrinkles and reduced elasticity. Various antiaging approaches, including topicals, energy-based procedures, and dermal fillers, can restore the molecular features of dermal aging with clinical efficacy. This review summarizes the current understanding of skin aging at the molecular level, and associated treatments, to put some of the new antiaging technology that has emerged in this rapidly expanding field into molecular context.

Hawthorn Polyphenol Extract Inhibits UVB-Induced Skin Photoaging by Regulating MMP Expression and Type I Procollagen Production in Mice

Ultraviolet (UV) B radiation can cause skin aging by increasing matrix metalloproteinase (MMP) production and collagen degradation, leading to the formation of wrinkles. This study investigated whether hawthorn polyphenol extract (HPE) protects against UVB-induced skin photoaging using HaCaT human keratinocytes, normal human dermal fibroblasts (HDFs), and mice. Analysis of the phenol composition of HPE by high-performance liquid chromatography-mass spectrometry showed that chlorogenic acid (13.5%), procyanidin B2 (19.2%), and epicatechin (18.8%) collectively accounted for 51.4% of total phenol content and represent the active ingredients of hawthorn fruit. A cell viability assay revealed that HPE treatment promoted cell proliferation in HaCaT cells and HDFs. On the other hand, MMP-1 and type I procollagen production was decreased and increased, respectively, in UVB-exposed cells treated with HPE as compared with those without treatment, as determined by enzyme-linked immunosorbent assay. Hematoxylin and eosin and Weigert staining of dermal tissue specimens from mice demonstrated that HPE also reversed UVB-induced epidermal thickening and dermal damage. The increase in production of reactive oxygen species and decrease in antioxidant enzyme activity as well as the increase in nuclear factor-κB activation and mitogen-activated protein kinase phosphorylation induced by UVB irradiation were reversed by HPE (100 or 300 mg/kg body weight), which also suppressed MMP expression and stimulated the production of type I procollagen in the dorsal skin of UVB-irradiated mice. These results suggest that HPE is a natural product that can prevent UVB radiation-induced skin photoaging.

(2E,5E)-2,5-Bis(3-hydroxy-4-methoxybenzylidene) cyclopentanone Exerts Anti-Melanogenesis and Anti-Wrinkle Activities in B16F10 Melanoma and Hs27 Fibroblast Cells

Ultraviolet (UV) radiation exposure is the primary cause of extrinsic skin aging, which results in skin hyperpigmentation and wrinkling. In this study, we investigated the whitening effect of (2E,5E)-2,5-bis(3-hydroxy-4-methoxybenzylidene)cyclopentanone (BHCP) on B16F10 melanoma and its anti-wrinkle activity on Hs27 fibroblasts cells. BHCP was found to potently inhibit tyrosinase, with 50% inhibition concentration (IC₅₀) values of 1.10 µM and 8.18 µM for monophenolase (l-tyrosine) and diphenolase (l-DOPA), and the enzyme kinetics study revealed that BHCP is a competitive-type tyrosinase inhibitor. Furthermore, BHCP significantly inhibited melanin content and cellular tyrosinase activity, and downregulated the levels of microphthalmia-associated transcription factor (MITF), phosphorylated levels of cAMP response element-binding (CREB) protein, and tyrosinase in α-melanocyte stimulating hormone (α-MSH)-induced B16F10 melanoma cells. Moreover, BHCP inhibited the phosphorylation of p65 and expression of matrix metalloproteinases (MMP-1, MMP-9, MMP-12, and MMP-13) in Hs27 fibroblasts stimulated with UV radiation. Therefore, our results demonstrate that BHCP may be a good candidate for the development of therapeutic agents for diseases associated with hyperpigmentation and wrinkling.

Molecular modeling of non-covalent binding of Ligustrum lucidum secoiridoid glucosides to AP-1/matrix metalloproteinase pathway components

Ligustrum lucidum secoiridoid glucosides have been demonstrated to treat various types of diseases such as inflammation, pain, hepatotoxicity and hyperlipidermic as well as tonic for liver and kidney. Matrix metalloproteinases (MMPs) play a key role upon the pathology of photoaging. The present computational study showed that among the six secoiridoid glucosides (ligustroside, lucidumoside A, lucidumoside C, neonuezhenide, oleoside dimethylester, and oleuropein), ligustroside and lucidumoside A competitively inhibit all MMP-1, MMP-3, and MMP-9 activities in the docking models. The molecular docking analysis revealed a network of interactions between MMP-1, MMP-3, and MMP-9 and the ligands; ligustroside and lucidumoside A, and oxygen-containing and hydrophobic functional groups appear to be responsible for these enhanced interactions. The effect of ligustroside and lucidumoside A on the transcription factor AP-1 action was also investigated using molecular docking and dynamics simulations. The experiments suggested that inhibition of an AP-1-DNA complex formation could be on account of the direct interference of AP-1 binding onto the DNA binding sequence by ligustroside and lucidumoside A. The results suggest that both compounds have the highest potential for application as an anti-aging agent with the MMP inhibitory and anti-transcriptional activities.

Inhibition of UVB-induced pro-inflammatory cytokines and MMP expression by Zanthoxylum rhetsa bark extract and its active constituent hesperidin

The antiphoto aging property of Zanthoxylum rhetsa obtained from Pangkor Island, Malaysia, was evaluated. Solvent fractions of different polarity obtained from the methanolic extract of the bark material were initially tested for anticollagenase and antielastase activities. The ethyl acetate fraction showed bioactivity against the protease enzymes. Hence, it was subjected to further purification via column chromatography, to yield a major constituent, hesperidin. Subsequently, the ethyl acetate fraction and hesperidin were tested for their effects against UVB-induced cytotoxicity and expressions of inflammatory cytokines (IL-6, IL-1β, and TNF-α), NF-κB, and MMPs (MMP1, 3, and 9) in human dermal fibroblasts (HDF). Both fraction and pure compound prevented UVB-induced cytotoxicity in HDF cells, in a dose dependent manner. Moreover, the ethyl acetate fraction inhibited the increase of pro-inflammatory cytokines induced by UVB to a level similar to the control (without UV treatment). Additionally, the fraction significantly inhibited the expressions of NF-κB, MMP 1, MMP 3, and MMP 9 in HDF cells treated with UVB. Similar effects were observed with hesperidin. The results obtained suggested that the ethyl acetate fraction of Z. rhetsa and its bioactive constituent, hesperidin, have the potential to be used as active ingredients in sunscreen and antiphoto aging formulations.

Nutraceuticals for Skin Care: A Comprehensive Review of Human Clinical Studies

The skin is the body’s largest organ, it participates in sensitivity and offers protection against microorganisms, chemicals and ultraviolet (UV) radiation. Consequently, the skin may suffer alterations such as photo-ageing, immune dysfunction and inflammation which may significantly affect human health. Nutraceuticals represent a promising strategy for preventing, delaying, or minimising premature ageing of the skin and also to alleviate certain skin disorders. Among them, bioactive peptides and oligosaccharides, plant polyphenols, carotenoids, vitamins and polyunsaturated fatty acids are the most widely used ingredients. Supplementation with these products has shown evidence of having an effect on the signs of ageing and protection against UV radiation ageing in several human trials. In this review, the most relevant human studies on skin nutraceuticals are evaluated and the statistical resolution, biological relevance of their results, and, the trial protocols are discussed. In conclusion, quality and rigorousness of the trials must be improved to build credible scientific evidence for skin nutraceuticals and to establish a cause-effect relationship between the ingredients the beneficial effects for the skin.

PER, a Circadian Clock Component, Mediates the Suppression of MMP-1 Expression in HaCaT Keratinocytes by cAMP

Skin circadian clock system responds to daily changes, thereby regulating skin functions. Exposure of the skin to UV irradiation induces the expression of matrix metalloproteinase-1 (MMP-1) and causes DNA damage. It has been reported both DNA repair and DNA replication are regulated by the circadian clock in mouse skin. However, the molecular link between circadian clock and MMP-1 has little been investigated. We found PERIOD protein, a morning clock component, represses the expression of MMP-1 in human keratinocytes by using a PER-knockdown strategy. Treatment with siPer3 alleviated the suppression of MMP-1 expression induced by forskolin. Results revealed PER3 suppresses the expression of MMP-1 via cAMP signaling pathway. Additionally, we screened for an activator of PER that could repress the expression of MMP-1 using HaCaT cell line containing PER promoter-luciferase reporter gene. Results showed Lespedeza capitate extract (LCE) increased PER promoter activity. LCE inhibited the expression of MMP-1 and its effect of LCE was abolished in knockdown of PER2 or PER3, demonstrating LCE can repress the expression of MMP-1 through PER. Since circadian clock component PER can regulate MMP-1 expression, it might be a new molecular mechanism to develop therapeutics to alleviate skin aging and skin cancer.

Topical or oral treatment of peach flower extract attenuates UV-induced epidermal thickening, matrix metalloproteinase-13 expression and pro-inflammatory cytokine production in hairless mice skin

BACKGROUND/OBJECTIVES

Ultraviolet radiation (UV) is a major cause of skin photoaging. Previous studies reported that ethanol extract (PET) of Prunus persica (L.) Batsch flowers (PPF, peach flowers) and its subfractions, particularly the ethylacetate (PEA) and n-butanol extracts (PBT), have potent antioxidant activity and attenuate the UV-induced matrix metalloproteinase (MMP) expression in human skin cells. In this study, we investigated the protective activity of PPF extract against UV-induced photoaging in a mouse model.

MATERIALS/METHODS

Hairless mice were treated with PET or a mixture of PEA and PBT either topically or orally along with UV irradiation. Histological changes and biochemical alterations of mouse skin were examined. Major phenolic compounds in PPF extract were analyzed using an ACQUITY UPLC system.

RESULTS

The overall effects of topical and oral treatments with PPF extract on the UV-induced skin responses exhibited similar patterns. In both experiments, the mixture of PEA and PBT significantly inhibited the UV-induced skin and epidermal thickening, while PET inhibited only the UV-induced epidermal thickening. Treatment of PET or the mixture of PEA and PBT significantly inhibited the UV-induced MMP-13 expression, but not typeⅠ collagen expression. Topical treatment of the mixture of PEA and PBT with UV irradiation significantly elevated catalase, superoxide dismutase (SOD) and glutathione-peroxidase (GPx) activities in the skin compared to those in the UV irradiated control group, while oral treatment of the mixture of PEA and PBT or PET elevated only catalase and SOD activities, but not GPx. Thirteen phytochemical compounds including 4-O-caffeoylquinic acid, cimicifugic acid E and B, quercetin-3-O-rhamnoside and kaempferol glycoside derivatives were identified in the PPF extract.

CONCLUSIONS

These results demonstrate that treatment with PET or the mixture of PEA and PBT, both topically or orally, attenuates UV-induced photoaging via the cooperative interactions of phenolic components having anti-oxidative and collagen-protective activities.

Transglycosylation of gallic acid by using Leuconostoc glucansucrase and its characterization as a functional cosmetic agent

Gallic acid glycoside was enzymatically synthesized by using dextransucrase and sucrose from gallic acid. After purification by butanol partitioning and preparative HPLC, gallic acid glucoside was detected at m/z 355 (C₁₃, H₁₆, O₁₀, Na)⁺ by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The yield of gallic acid glucoside was found to be 35.7% (114 mM) by response surface methodology using a reaction mixture of 319 mM gallic acid, 355 mM sucrose, and 930 mU/mL dextransucrase. The gallic acid glucoside obtained showed 31% higher anti-lipid peroxidation and stronger inhibition (Ki = 1.23 mM) against tyrosinase than that shown by gallic acid (Ki = 1.98 mM). In UVB-irradiated human fibroblast cells, gallic acid glucoside lowered matrix metalloproteinase-1 levels and increased the collagen content, which was indicative of a stronger anti-aging effect than that of gallic acid or arbutin. These results indicated that gallic acid glucoside is likely a superior cosmetic ingredient with skin-whitening and anti-aging functions.

A quantitative and non-contact technique to characterise microstructural variations of skin tissues during photo-damaging process based on Mueller matrix polarimetry

Skin tissue consists of collagen and elastic fibres, which are highly susceptible to damage when exposed to ultraviolet radiation (UVR), leading to skin aging and cancer. However, a lack of non-invasive detection methods makes determining the degree of UVR damage to skin in real time difficult. As one of the fundamental features of light, polarization can be used to develop imaging techniques capable of providing structural information about tissues. In particular, Mueller matrix polarimetry is suitable for detecting changes in collagen and elastic fibres. Here, we demonstrate a novel, quantitative, non-contact and in situ technique based on Mueller matrix polarimetry for monitoring the microstructural changes of skin tissues during UVR-induced photo-damaging. We measured the Mueller matrices of nude mouse skin samples, then analysed the transformed parameters to characterise microstructural changes during the skin photo-damaging and self-repairing processes. Comparisons between samples with and without the application of a sunscreen showed that the Mueller matrix-derived parameters are potential indicators for fibrous microstructure in skin tissues. Histological examination and Monte Carlo simulations confirmed the relationship between the Mueller matrix parameters and changes to fibrous structures. This technique paves the way for non-contact evaluation of skin structure in cosmetics and dermatological health.

Whitening and anti-wrinkle activities of ferulic acid isolated from Tetragonia tetragonioides in B16F10 melanoma and CCD-986sk fibroblast cells

Ferulic acid isolated from Tetragonia tetragonioides was tested for its whitening effect on the B16F10 mouse melanoma cell line and its anti-wrinkle activity on the CCD-986sk human dermal fibroblast cell line. Ferulic acid, one of the primary phenolic compounds that can be isolated from T. tetragonioides, has been reported to show potential as a functional food, for its whitening effect and anti-wrinkle activity. To measure its whitening and anti-wrinkle activities, cells were treated with ferulic acid isolated from T. tetragonioides at concentrations between 5 and 20 μM. Ferulic acid showed no cytotoxicity at concentrations up to 20 μM. Ferulic acid inhibited melanin synthesis, tyrosinase expression, and microphthalmia transcription factor expression in B16F10 cells stimulated with α-melanocyte stimulating hormone. Ferulic acid induced procollagen synthesis, hyaluronic acid synthesis, tissue inhibitor of metalloproteinase synthesis, and inhibited matrix metalloproteinase (MMP)-1 and MMP-9 expression in CCD-986sk cells stimulated with UV-B. On the basis of these results, we conclude that ferulic acid isolated from T. tetragonioides shows potential for use as a functional food, with whitening and anti-wrinkle activities.

Matrix Metalloproteinases-7 and Kidney Fibrosis

Matrix metalloproteinase-7 (MMP-7) is a secreted zinc- and calcium-dependent endopeptidase that degrades a broad range of extracellular matrix substrates and additional substrates. MMP-7 playsa crucial role in a diverse array of cellular processes and appears to be a key regulator of fibrosis in several diseases, including pulmonary fibrosis, liver fibrosis, and cystic fibrosis. In particular, the relationship between MMP-7 and kidney fibrosis has attracted significant attention in recent years. Growing evidence indicates that MMP-7 plays an important role in the pathogenesis of kidney fibrosis. Here, we summarize the recent progress in the understanding of the role of MMP-7 in kidney fibrosis. In particular, we discuss how MMP-7 contributes to kidney fibrotic lesions via the following three pathways: epithelial-mesenchymal transition (EMT), transforming growth factor-beta (TGF-β) signaling, and extracellular matrix (ECM) deposition. Further dissection of the crosstalk among and regulation of these pathways will help clinicians and researchers develop effective therapeutic approaches for treating chronic kidney disease.

Physicochemical properties and antioxidant activities of polysaccharides from Gynura procumbens leaves by fractional precipitation

Four new polysaccharides (GPP-20, GPP-40, GPP-60 and GPP-80) were fractionated from Gynura procumbens leaves by 20%, 40%, 60% and 80% (v/v) ethanol, successively. Their physicochemical properties including the contents of neutral sugar, uronic acid and protein, as well as the monosaccharide composition were determined. In addition, the antioxidant activities of them were investigated via the reducing power assay and scavenging capacities of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and hydroxyl free radicals, respectively. The results indicated that apart from neutral sugar, they all contained uronic acids and proteins in their structures, which were further proved by the UV-vis and FT-IR spectra. Monosaccharide composition analysis implied that they all belonged to heteropolysaccharides consisted of arabinose, galactose, glucose, xylose and galacturonic acid with different types and ratios. What's more, GPP-20, GPP-40 and GPP-80 always exhibited better antioxidant activities than GPP-60 among these three antioxidant assays in vitro.

Tiron Inhibits UVB-Induced AP-1 Binding Sites Transcriptional Activation on MMP-1 and MMP-3 Promoters by MAPK Signaling Pathway in Human Dermal Fibroblasts

Recent research found that Tiron was an effective antioxidant that could act as the intracellular reactive oxygen species (ROS) scavenger or alleviate the acute toxic metal overload in vivo. In this study, we investigated the inhibitory effect of Tiron on matrix metalloproteinase (MMP)-1 and MMP-3 expression in human dermal fibroblast cells. Western blot and ELISA analysis revealed that Tiron inhibited ultraviolet B (UVB)-induced protein expression of MMP-1 and MMP-3. Real-time quantitative PCR confirmed that Tiron could inhibit UVB-induced mRNA expression of MMP-1 and MMP-3. Furthermore, Tiron significantly blocked UVB-induced activation of the MAPK signaling pathway and activator protein (AP)-1 in the downstream of this transduction pathway in fibroblasts. Through the AP-1 binding site mutation, it was found that Tiron could inhibit AP-1-induced upregulation of MMP-1 and MMP-3 expression through blocking AP-1 binding to the AP-1 binding sites in the MMP-1 and MMP-3 promoter region. In conclusion, Tiron may be a novel antioxidant for preventing and treating skin photoaging UV-induced.

Role of Matrix Metalloproteinases in Photoaging and Photocarcinogenesis

Matrix metalloproteinases (MMPs) are zinc-containing endopeptidases with an extensive range of substrate specificities. Collectively, these enzymes are able to degrade various components of extracellular matrix (ECM) proteins. Based on their structure and substrate specificity, they can be categorized into five main subgroups, namely (1) collagenases (MMP-1, MMP-8 and MMP-13); (2) gelatinases (MMP-2 and MMP-9); (3) stromelysins (MMP-3, MMP-10 and MMP-11); (4) matrilysins (MMP-7 and MMP-26); and (5) membrane-type (MT) MMPs (MMP-14, MMP-15, and MMP-16). The alterations made to the ECM by MMPs might contribute in skin wrinkling, a characteristic of premature skin aging. In photocarcinogenesis, degradation of ECM is the initial step towards tumor cell invasion, to invade both the basement membrane and the surrounding stroma that mainly comprises fibrillar collagens. Additionally, MMPs are involved in angiogenesis, which promotes cancer cell growth and migration. In this review, we focus on the present knowledge about premature skin aging and skin cancers such as basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma, with our main focus on members of the MMP family and their functions.

Ellagic acid plays a protective role against UV-B-induced oxidative stress by up-regulating antioxidant components in human dermal fibroblasts

Ellagic acid (EA), an antioxidant polyphenolic constituent of plant origin, has been reported to possess diverse pharmacological properties, including anti-inflammatory, anti-tumor and immunomodulatory activities. This work aimed to clarify the skin anti-photoaging properties of EA in human dermal fibroblasts. The skin anti-photoaging activity was evaluated by analyzing the reactive oxygen species (ROS), matrix metalloproteinase-2 (MMP-2), total glutathione (GSH) and superoxide dismutase (SOD) activity levels as well as cell viability in dermal fibroblasts under UV-B irradiation. When fibroblasts were exposed to EA prior to UV-B irradiation, EA suppressed UV-B-induced ROS and proMMP-2 elevation. However, EA restored total GSH and SOD activity levels diminished in fibroblasts under UV-B irradiation. EA had an up-regulating activity on the UV-B-reduced Nrf2 levels in fibroblasts. EA, at the concentrations used, was unable to interfere with cell viabilities in both non-irradiated and irradiated fibroblasts. In human dermal fibroblasts, EA plays a defensive role against UV-B-induced oxidative stress possibly through an Nrf2-dependent pathway, indicating that this compound has potential skin antiphotoaging properties.

Gynura procumbens: An Overview of the Biological Activities

Gynura procumbens (Lour.) Merr. (Family Asteraceae) is a medicinal plant commonly found in tropical Asia countries such as China, Thailand, Indonesia, Malaysia, and Vietnam. Traditionally, it is widely used in many different countries for the treatment of a wide variety of health ailments such as kidney discomfort, rheumatism, diabetes mellitus, constipation, and hypertension. Based on the traditional uses of G. procumbens, it seems to possess high therapeutic potential for treatment of various diseases making it a target for pharmacological studies aiming to validate and provide scientific evidence for the traditional claims of its efficacy. Although there has been considerable progress in the research on G. procumbens, to date there is no review paper gathering the reported biological activities of G. procumbens. Hence, this review aims to provide an overview of the biological activities of G. procumbens based on reported in vitro and in vivo studies. In brief, G. procumbens has been reported to exhibit antihypertensive, cardioprotective, antihyperglycemic, fertility enhancement, anticancer, antimicrobial, antioxidant, organ protective, and antiinflammatory activity. The commercial applications of G. procumbens have also been summarized in this paper based on existing patents. The data compiled illustrate that G. procumbens is a potential natural source of compounds with various pharmacological actions which can be utilized for the development of novel therapeutic agents.

Hypoglycemic and anti-hyperglycemic study of Gynura procumbens leaf extracts

OBJECTIVE

To study the antidiabetic activity of Gynura procumbens (G. procumbens) used in the traditional management of diabetes in Southern Asia.

METHODS

G. procumbens leaves were extracted sequentially with graded percentage of ethanol in water (95%, 75%, 50%, 25% and 0%), and the extracts were tested for antidiabetic activity using acute (7 h), subcutaneous glucose tolerance test and sub-chronic (14 d) test in non-diabetic and streptozotocin-induced diabetic rats. The extracts were further subjected to phytochemical studies.

RESULTS

In acute dose (1 g/kg), the extracts significantly lowered fasting blood glucose (FBG) in streptozotocin-induced diabetic rats (P<0.05). However, the FBG-lowering effect of the 25% extract compared to the other extracts, was rapid (47% after 2 h) and the highest: 53%, 53% and 60% in the 3rd, 5th, and 7th h, respectively (P<0.05), comparable only to the effect of metformin. Furthermore, the extracts suppressed peak FBG in subcutaneous glucose tolerance test, but only the 0% and 25% extracts, and metformin sustained the decrease until the 90th min (P<0.05). Moreover, in the 14 days study, the 25% extract exerted the highest FBG-lowering effect, namely 49.38% and 65.43% on days 7 and 14, respectively (P<0.05), similar to the effect of metformin (46.26% and 65.42%). Total flavanoid and phenolic contents in the extracts were found to decrease with increase in polarity of extraction solvents. The composition of reference compounds (chlorogenic acid, rutin, astragalin and kaempferol-3-O-rutinoside) followed a similar trend.

CONCLUSIONS

G. procumbens contains antidiabetic principles, most extracted in 25% ethanol. Interaction among active components appears to determine the antidiabetic efficacy, achieved likely by a metformin-like mechanism.

Suppressive properties of ginsenoside Rb2, a protopanaxadiol-type ginseng saponin, on reactive oxygen species and matrix metalloproteinase-2 in UV-B-irradiated human dermal keratinocytes

Ginsenosides, also known as ginseng saponins, are the principal bioactive ingredients of ginseng, which are responsible for its diverse pharmacological activities. The present work aimed to assess skin anti-photoaging properties of ginsenoside Rb2 (Rb2), one of the predominant protopanaxadiol-type ginsenosides, in human epidermal keratinocyte HaCaT cells under UV-B irradiation. When the cultured keratinocytes were subjected to Rb2 prior to UV-B irradiation, Rb2 displayed suppressive activities on UV-B-induced reactive oxygen species elevation and matrix metalloproteinase-2 expression and secretion. However, Rb2 at the used concentrations was unable to modulate cellular survivals in the UV-B-irradiated keratinocytes. In brief, Rb2 possesses a protective role against the photoaging of human keratinocyte cells under UV-B irradiation.

Stereoselective skin anti-photoaging properties of ginsenoside Rg3 in UV-B-irradiated keratinocytes

Ginsenosides are major bioactive constituents that are responsible for the diverse pharmacological activities of ginseng. This work aimed to assess the skin anti-photoaging activities of the two stereoisomeric forms of ginsenoside Rg3, 20(S)-Rg3 and 20(R)-Rg3. When the two Rg3 stereoisomers were added to cultured human keratinocyte HaCaT cells prior to irradiation with 70 mJ/cm(2) UV-B, 20(S)-Rg3, but not 20(R)-Rg3, decreased the UV-B-induced intracellular reactive oxygen species (ROS) levels in a concentration-dependent manner, as detected by both fluorometric and confocal microscopic analyses. Likewise, 20(S)-Rg3, but not 20(R)-Rg3, decreased the UV-B-induced ROS levels in human dermal fibroblast cells. Both stereoisomers were unable to modulate the nitric oxide levels in HaCaT cells under UV-B irradiation, and induced no cytotoxicity in cultured keratinocytes and fibroblasts. 20(S)-Rg3 suppressed the UV-B-induced matrix metalloproteinase (MMP)-2 activities in HaCaT cells. Taken together, these results indicate that 20(S)-Rg3 possesses both ROS-scavenging and MMP-2 inhibitory activities, while 20(R)-Rg3 possesses neither activity. These findings imply that ginsenoside Rg3 stereoselectively demonstrates skin anti-photoaging activities.

Prevention of UV radiation-induced cutaneous photoaging in mice by topical administration of patchouli oil

ETHNOPHARMACOLOGICAL RELEVANCE

Pogostemon cablin has been widely used in traditional Chinese medicine for the treatment of many diseases, including skin disorders. In the skin beauty and care prescriptions, Pogostemon cablin is one of the top ten frequently used traditional Chinese medicines.

AIM OF THE STUDY

The present study was aimed to investigate the protective effects of the essential oil of Pogostemon cablin (patchouli oil, PO) against UV-induced skin photoaging in mice.

MATERIALS AND METHODS

To ensure the quality of PO, the chemical compositions of PO were identified, and the content of its chemical marker patchouli alcohol was determined, which was around 28.2% (g/g) in PO. During the experiment period, the dorsal depilated skin of mice was treated with PO for two hours prior to UV irradiation. Then the protective effects of PO on UV-induced skin photoaging were determined by macroscopic and histological evaluations, skin elastic test, collagen content determination and biochemical assays of malondiaidehyde (MDA) content, activities of anti-oxidative indicators including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT).

RESULTS

Compared to UV exposure groups, present results showed that topical administration of PO, especially at dose of 6mg/mouse and 9mg/mouse, significantly inhibited the increase in skin wrinkle formation, alleviated the reduction in skin elasticity and increased the collagen content by about 21.9% and 26.3%, respectively. We also found that application of 6-9mg/mouse PO could not only decrease the epidermal thickness by about 32.6%, but also prevent the UV-induced disruption of collagen fibers and elastic fibers. Furthermore, the content of MDA was decreased by almost 26.5% and activities of SOD, GSH-Px and CAT were significantly up-regulated after the treatment of PO.

CONCLUSION

Results of present study revealed that PO was capable of maintaining skin structural integrity caused by UV irradiation and it was useful in preventing photoaging. These protective effects of PO were possibly due to its anti-oxidative property. Therefore, we suggested that PO should be viewed as a potential therapeutic agent for preventing photoaging.

Potent antioxidative and UVB protective effect of water extract of Eclipta prostrata L

Oxidative stress, including Ultraviolet (UV) irradiation-induced skin damage, is involved in numerous diseases. This study demonstrates that water extract of Eclipta prostrata L. (WEP) has a potent effect in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide radicals, and chelating ferrous ion, exhibiting IC₅₀ values of 0.23 mg/mL, 0.48 mg/mL, and 1.25 mg/mL, respectively. The WEP total phenol content was 176.45 mg gallic acid equivalents (GAE)/g sample. Chlorogenic acid, a component of the plant's active ingredients, was determined by HPLC and antioxidative assay. However, no caffeic acid, stigmasterol, or wedelolactone was present in WEP. WEP absorbs both UVA and UVB irradiation, and furthermore, the extract shows a dose-dependent response in the protection of HaCaT human keratinocytes and mouse fibroblasts 3T3 cells against UVB-induced cytotoxicity, which may result from a synergistic effect between chlorogenic acid and other active components present in WEP.

Potassium channel openers and prostacyclin play a crucial role in mediating the vasorelaxant activity of Gynura procumbens

Background

Previous studies of Gynura procumbens (G. procumbens) have shown that partially purified fractions of the leaves are capable of lowering the blood pressure of rats by inhibiting angiotensin-converting enzymic activity and causing vasodilatation. The objectives of this study were therefore to further purify the active compounds that exhibited selective effects on blood vessels, determine the mechanism of actions, and to qualitatively analyse the putative compounds present.

Methods

The butanolic fraction (BU) of the crude ethanolic extract was purified using column chromatography to obtain several sub-fractions of different polarities. The in vitro effects of BU and the sub-fractions on vascular tension were subsequently determined using isolated rat thoracic aortic rings. The most potent sub-fraction (F1) alone was then investigated for its mechanisms of the vasorelaxant activity. In another experiment, thin-layer chromatography was used to qualitatively analyse the active compounds found in F1.

Results

The BU and the sub-fractions ranging from 10^-7 to 10^-2 g/ml significantly (p < 0.05) inhibited the sustained tonic contractions induced by phenylephrine and potassium chloride in a concentration-dependent manner with various degree of potency. The most potent sub-fraction (F1) antagonised the calcium-induced vasocontractions (1 x 10^-4 – 1 x 10^-2 M) in calcium-free with high concentration of potassium as well as in calcium- and potassium-free Krebs-Henseleit solutions. Contractions induced by noradrenaline and caffeine were not affected by F1. The vasorelaxing effect caused by F1 was significantly attenuated with preincubation of potassium channel blockers (glibenclamide and 4-aminopyridine) and prostacyclin inhibitor (indomethacin) while it was not affected by preincubation with tetraethylammonium, l-nitro-arginine methyl esther, propanolol, atropine, oxadiazolo quinoxalin one and methylene blue. The qualitative phytochemical analysis of F1 indicated the presence of flavonoids.

Conclusion

These results confirm previous findings that G. procumbens causes vasodilatory effects by blocking calcium channels. In addition, the present study further demonstrates that the vasodilatory effect of G. procumbens may also be due to the opening of potassium channels and the stimulation of prostacyclin production. The putative compounds are probably flavonoids in nature.

Gynura procumbens ethanolic extract suppresses osteosarcoma cell proliferation and metastasis in vitro

Gynura procumbens is a traditional herb used for the treatment of inflammation, rheumatism and viral infections, although the antitumor effect and its potential mechanisms of action remain unclear. In the present study, the antitumor effect of Gynura procumbens ethanolic extract (GPE) on the osteosarcoma (OS) cell line, U2-OS, was investigated in vitro. Cell proliferation and apoptosis were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays, respectively. Transwell invasion and wound healing assays were performed to investigate the invasion and migration of the U2-OS cells. The results showed that GPE was able to inhibit U2-OS cell proliferation and metastasis and induce cell apoptosis. Furthermore, the expression of the NF-κBp65 protein was detected by western blotting to evaluate the effects of GPE on the nuclear transfer of NF-κB. It was demonstrated that the expression of the NF-κBp65 protein was significantly decreased by GPE. This indicated that GPE was able to inhibit the nuclear transfer of NF-κB. The study shows that GPE is able to induce apoptosis and suppress proliferation and metastasis in U2-OS cells via the inhibition of the nuclear translocation of NF-κB.

Topical application of Acalypha indica accelerates rat cutaneous wound healing by up-regulating the expression of Type I and III collagen

ETHNOPHARMACOLOGICAL RELEVANCE

Acalypha indica Linn. (Acalypha indica) vernacularly called Kuppaimeni in Tamil, has been used as a folklore medicine since ages for the treatment of wounds by tribal people of Tamil Nadu, Southern India. The present study investigates the biochemical and molecular rationale behind the healing potential of Acalypha indica on dermal wounds in rats.

MATERIAL AND METHODS

Acalypha indica extract (40 mg/kg body weight) was applied topically once a day on full-thickness excision wounds created on rats. The wound tissue was removed and used for estimation of various biochemical and biophysical analyses and to observe histopathological changes with and with-out extract treatment. The serum levels of pro-inflammatory cytokine tumor necrosis factor (TNF-α) was measured at 12 h, 24 h, 48 h and 72 h post-wounding using ELISA. Reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed to study the expression pattern of transforming growth factor [TGF-β1], collagen 1 α (I) [Col 1 α (I)] and collagen 3 α (I) [Col 3 α (I)]. Likewise, linear incision wounds were created and treated with the extract and used for tensile strength measurements.

RESULTS

Wound healing in control rats was characterized by less inflammatory cell infiltration, lack of granulation tissue formation, deficit of collagen and significant decrease in biomechanical strength of wounds. Acalypha indica treatment mitigated the oxidative stress and decreased lipid peroxidation with concomitant increase in ascorbic acid levels. It also improved cellular proliferation, increased TNF-α levels during early stages of wound healing, up-regulated TGF-β1 and elevated collagen synthesis by markedly increasing the expression of Col 1 α (I) and Col 3 α (I). Increased rates of wound contraction, epithelialization, enhanced shrinkage temperature and high tensile strength were observed in the extract treated rats.

CONCLUSION

Acalypha indica extract was shown to augment the process of dermal wound healing by its ability to increase collagen synthesis through up-regulation of key players in different phases of wound healing and by its antioxidative potential.

Ixora parviflora Protects against UVB-Induced Photoaging by Inhibiting the Expression of MMPs, MAP Kinases, and COX-2 and by Promoting Type I Procollagen Synthesis

Ixora parviflora with high polyphenol content exhibited antioxidant activity and reducing UVB-induced intracellular reactive oxygen species production. In this study, results of the photoaging screening experiments revealed that IPE at 1000 μg/mL reduced the activity of bacterial collagenase by 92.7 ± 4.2% and reduced the activity of elastase by 32.6 ± 1.4%. Therefore, we investigated the mechanisms by which IPE exerts its anti-photoaging activity. IPE at 1 μg/mL led to an increase in type I procollagen expression and increased total collagen synthesis in fibroblasts at 5 μg/mL. We found that IPE inhibited MMP-1, MMP-3, and MMP-9 expression at doses of 1, 5, and 10 μg/mL, respectively, in fibroblasts exposed to UV irradiation (40 mJ/cm(2)). Gelatin zymography assay showed that IPE at 50 μg/mL inhibited MMP-9 secretion/activity in cultured fibroblasts after UVB exposure. In addition, IPE inhibited the phosphorylation of p38, ERK, and JNK induced by UVB. Furthermore, IPE inhibited the UVB-induced expression of Smad7. In addition, IPE at 1 μg/mL inhibited NO production and COX-2 expression in UV-exposed fibroblasts. These findings show that IPE exhibits anti-inflammatory and anti-photoaging activities, indicating that IPE could be a potential anti-aging agent.