Therapeutic Potential and Mechanisms of Rosmarinic Acid and the Extracts of Lamiaceae Plants for the Treatment of Fibrosis of Various Organs.

Fibrosis, which causes structural hardening and functional degeneration in various organs, is characterized by the excessive production and accumulation of connective tissue containing collagen, alpha-smooth muscle actin (α-SMA), etc. In traditional medicine, extracts of medicinal plants or herbal prescriptions have been used to treat various fibrotic diseases. The purpose of this narrative review is to discuss the antifibrotic effects of rosmarinic acid (RA) and plant extracts that contain RA, as observed in various experimental models. RA, as well as the extracts of Glechoma hederacea, Melissa officinalis, Elsholtzia ciliata, Lycopus lucidus, Ocimum basilicum, Prunella vulgaris, Salvia rosmarinus (Rosmarinus officinalis), Salvia miltiorrhiza, and Perilla frutescens, have been shown to attenuate fibrosis of the liver, kidneys, heart, lungs, and abdomen in experimental animal models. Their antifibrotic effects were associated with the attenuation of oxidative stress, inflammation, cell activation, epithelial-mesenchymal transition, and fibrogenic gene expression. RA treatment activated peroxisomal proliferator-activated receptor gamma (PPARγ), 5' AMP-activated protein kinase (AMPK), and nuclear factor erythroid 2-related factor 2 (NRF2) while suppressing the transforming growth factor beta (TGF-ß) and Wnt signaling pathways. Interestingly, most plants that are reported to contain RA and exhibit antifibrotic activity belong to the family Lamiaceae. This suggests that RA is an active ingredient for the antifibrotic effect of Lamiaceae plants and that these plants are a useful source of RA. In conclusion, accumulating scientific evidence supports the effectiveness of RA and Lamiaceae plant extracts in alleviating fibrosis and maintaining the structural architecture and normal functions of various organs under pathological conditions.

Insights into How Plant-Derived Extracts and Compounds Can Help in the Prevention and Treatment of Keloid Disease: Established and Emerging Therapeutic Targets.

Keloid is a disease in which fibroblasts abnormally proliferate and synthesize excessive amounts of extracellular matrix, including collagen and fibronectin, during the healing process of skin wounds, causing larger scars that exceed the boundaries of the original wound. Currently, surgical excision, cryotherapy, radiation, laser treatment, photodynamic therapy, pressure therapy, silicone gel sheeting, and pharmacotherapy are used alone or in combinations to treat this disease, but the outcomes are usually unsatisfactory. The purpose of this review is to examine whether natural products can help treat keloid disease. I introduce well-established therapeutic targets for this disease and various other emerging therapeutic targets that have been proposed based on the phenotypic difference between keloid-derived fibroblasts (KFs) and normal epidermal fibroblasts (NFs). We then present recent studies on the biological effects of various plant-derived extracts and compounds on KFs and NFs. Associated ex vivo, in vivo, and clinical studies are also presented. Finally, we discuss the mechanisms of action of the plant-derived extracts and compounds, the pros and cons, and the future tasks for natural product-based therapy for keloid disease, as compared with existing other therapies. Extracts of Astragalus membranaceus, Salvia miltiorrhiza, Aneilema keisak, Galla Chinensis, Lycium chinense, Physalis angulate, Allium sepa, and Camellia sinensis appear to modulate cell proliferation, migration, and/or extracellular matrix (ECM) production in KFs, supporting their therapeutic potential. Various phenolic compounds, terpenoids, alkaloids, and other plant-derived compounds could modulate different cell signaling pathways associated with the pathogenesis of keloids. For now, many studies are limited to in vitro experiments; additional research and development are needed to proceed to clinical trials. Many emerging therapeutic targets could accelerate the discovery of plant-derived substances for the prevention and treatment of keloid disease. I hope that this review will bridge past, present, and future research on this subject and provide insight into new therapeutic targets and pharmaceuticals, aiming for effective keloid treatment.

Identification of p-Coumaric Acid and Ethyl p-Coumarate as the Main Phenolic Components of Hemp (Cannabis sativa L.) Roots.

Hemp (Cannabis sativa L.) contains a variety of secondary metabolites, including cannabinoids, such as psychoactive (-)-trans-Δ9-tetrahydrocannabinol. The present study was conducted to identify the major phenolic components contained in hemp root, which has been relatively under-researched compared to other parts of hemp. The aqueous ethanol extract of hemp roots was fractionated into methylene chloride (MC), ethyl acetate (EA), and water (WT) fractions, and high-performance liquid chromatography with photodiode array detection (HPLC-DAD) analysis was performed. The main ultraviolet (UV)-absorbing phenolic compound contained in the EA fraction was identified as p-coumaric acid by comparing the retention time and UV absorption spectrum with a standard. Silica gel column chromatography was performed to isolate a hydrophobic derivative of p-coumaric acid contained in the MC fraction. Nuclear magnetic resonance (NMR) analysis identified the isolated compound as ethyl p-coumarate. For comparative purposes, ethyl p-coumarate was also chemically synthesized by the esterification reaction of p-coumaric acid. The content of p-coumaric acid and ethyl p-coumarate in the total extract of hemp root was estimated to be 2.61 mg g-1 and 6.47 mg g-1, respectively, by HPLC-DAD analysis. These values correspond to 84 mg Kg-1 dry root and 216 mg Kg-1 dry root, respectively. In conclusion, this study identified p-coumaric acid and ethyl p-coumarate as the main phenolic compounds contained in the hemp roots.

Siegesbeckiae Herba Extract and Chlorogenic Acid Ameliorate the Death of HaCaT Keratinocytes Exposed to Airborne Particulate Matter by Mitigating Oxidative Stress.

Airborne particulate matter with a size of 10 µm or less (PM10) can cause oxidative damages and inflammatory reactions in the skin. This study was conducted to discover natural products that are potentially useful in protecting the skin from PM10. Among the hot water extracts of a total of 23 medicinal plants, Siegesbeckiae Herba extract (SHE), which showed the strongest protective effect against PM10 cytotoxicity, was selected, and its mechanism of action and active constituents were explored. SHE ameliorated PM10-induced cell death, lactate dehydrogenase (LDH) release, lipid peroxidation, and reactive oxygen species (ROS) production in HaCaT cells. SHE decreased the expression of KEAP1, a negative regulator of NRF2, and increased the expression of NRF2 target genes, such as HMOX1 and NQO1. SHE selectively induced the enzymes involved in the synthesis of GSH (GCL-c and GCL-m), the regeneration of GSH (GSR and G6PDH), and GSH conjugation of xenobiotics (GSTκ1), rather than the enzymes that directly scavenge ROS (SOD1, CAT, and GPX1). SHE increased the cellular content of GSH and mitigated the oxidation of GSH to GSSG caused by PM10 exposure. Of the solvent fractions of SHE, the n-butyl alcohol (BA) fraction ameliorated cell death in both the absence and presence of PM10. The BA fraction contained a high amount of chlorogenic acid. Chlorogenic acid reduced PM10-induced cell death, LDH release, and ROS production. This study suggests that SHE protects cells from PM10 toxicity by increasing the cellular antioxidant capacity and that chlorogenic acid may be an active phytochemical of SHE.

Mechanistic Basis and Clinical Evidence for the Applications of Nicotinamide (Niacinamide) to Control Skin Aging and Pigmentation.

Vitamin B3 (nicotinic acid, niacin) deficiency causes the systemic disease pellagra, which leads to dermatitis, diarrhea, dementia, and possibly death depending on its severity and duration. Vitamin B3 is used in the synthesis of the NAD+ family of coenzymes, contributing to cellular energy metabolism and defense systems. Although nicotinamide (niacinamide) is primarily used as a nutritional supplement for vitamin B3, its pharmaceutical and cosmeceutical uses have been extensively explored. In this review, we discuss the biological activities and cosmeceutical properties of nicotinamide in consideration of its metabolic pathways. Supplementation of nicotinamide restores cellular NAD+ pool and mitochondrial energetics, attenuates oxidative stress and inflammatory response, enhances extracellular matrix and skin barrier, and inhibits the pigmentation process in the skin. Topical treatment of nicotinamide, alone or in combination with other active ingredients, reduces the progression of skin aging and hyperpigmentation in clinical trials. Topically applied nicotinamide is well tolerated by the skin. Currently, there is no convincing evidence that nicotinamide has specific molecular targets for controlling skin aging and pigmentation. This substance is presumed to contribute to maintaining skin homeostasis by regulating the redox status of cells along with various metabolites produced from it. Thus, it is suggested that nicotinamide will be useful as a cosmeceutical ingredient to attenuate skin aging and hyperpigmentation, especially in the elderly or patients with reduced NAD+ pool in the skin due to internal or external stressors.

Ecklonia cava Extract and Dieckol Attenuate Cellular Lipid Peroxidation in Keratinocytes Exposed to PM10.

Airborne particulate matter can cause oxidative stress, inflammation, and premature skin aging. Marine plants such as Ecklonia cava Kjellman contain high amounts of polyphenolic antioxidants. The purpose of this study was to examine the antioxidative effects of E. cava extract in cultured keratinocytes exposed to airborne particulate matter with a diameter of <10 µm (PM10). After the exposure of cultured HaCaT keratinocytes to PM10 in the absence and presence of E. cava extract and its constituents, cell viability and cellular lipid peroxidation were assessed. The effects of eckol and dieckol on cellular lipid peroxidation and cytokine expression were examined in human epidermal keratinocytes exposed to PM10. The total phenolic content of E. cava extract was the highest among the 50 marine plant extracts examined. The exposure of HaCaT cells to PM10 decreased cell viability and increased lipid peroxidation. The PM10-induced cellular lipid peroxidation was attenuated by E. cava extract and its ethyl acetate fraction. Dieckol more effectively attenuated cellular lipid peroxidation than eckol in both HaCaT cells and human epidermal keratinocytes. Dieckol and eckol attenuated the expression of inflammatory cytokines such as tumor necrosis factor- (TNF-) α, interleukin- (IL-) 1ß, IL-6, and IL-8 in human epidermal keratinocytes stimulated with PM10. This study suggested that the polyphenolic constituents of E. cava, such as dieckol, attenuated the oxidative and inflammatory reactions in skin cells exposed to airborne particulate matter.

Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10.

Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 µM (PM10). PM10 stimulates the production of reactive oxygen species (ROS) and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE) on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and monocyte chemoattractant protein-1 (MCP-1), and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). PPE at 10-100 µg mL(-1) attenuated the production of ROS and the expression of TNF-α, IL-1ß, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 µg mL(-1)). PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter.

Scutellaria radix Extract as a Natural UV Protectant for Human Skin.

Ultraviolet (UV) radiation induces oxidative injury and inflammation in human skin. Scutellaria radix (SR, the root of Scutellaria baicalensis Georgi) contains flavonoids with high UV absorptivity and antioxidant properties. The purpose of this study was to examine the potential use of SR extract as an additive in cosmetic products for UV protection. SR extract and its butanol (BuOH) fraction strongly absorbed UV radiation and displayed free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radials and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals. They also attenuated the UV-induced death of HaCaT cells. Sunscreen creams, with or without supplementation of SR extract BuOH fraction, were tested in vivo in human trials to evaluate potential skin irritation and determine the sun protection factor (SPF). Both sunscreen creams induced no skin irritation. A sunscreen cream containing 24% ZnO showed an SPF value of 17.8, and it increased to 22.7 when supplemented with 5% SR extract BuOH fraction. This study suggests that SR-derived materials are useful as safe cosmetic additives that provide UV protection.

Gardenia jasminoides Extract Attenuates the UVB-Induced Expressions of Cytokines in Keratinocytes and Indirectly Inhibits Matrix Metalloproteinase-1 Expression in Human Dermal Fibroblasts.

Ultraviolet radiation (UV) is a major cause of photoaging, which also involves inflammatory cytokines and matrix metalloproteinases (MMP). The present study was undertaken to examine the UVB-protecting effects of yellow-colored plant extracts in cell-based assays. HaCaT keratinocytes were exposed to UVB in the absence or presence of plant extracts, and resulting changes in cell viability and inflammatory cytokine expression were measured. Of the plant extracts tested, Gardenia jasminoides extract showed the lowest cytotoxicity and dose-dependently enhanced the viabilities of UVB-exposed cells. Gardenia jasminoides extract also attenuated the mRNA expressions of interleukin-1 ß (IL-1 ß ) and tumor necrosis factor- α (TNF- α ) in HaCaT cells stimulated by UVB. Conditioned medium from UVB-exposed HaCaT cells was observed to stimulate MMP-1 protein expression in human dermal fibroblasts, and this effect was much smaller for the conditioned medium of HaCaT cells exposed to UVB in the presence of Gardenia jasminoides extract. Gardenia jasminoides extract also exhibited antioxidative and antiapoptotic effects in HaCaT cells exposed to UVB. These results indicated that UVB-induced injury and inflammatory responses of skin cells can be attenuated by yellow-colored plant extracts, such as Gardenia jasminoides extract.

Effects of resveratrol, oxyresveratrol, and their acetylated derivatives on cellular melanogenesis.

Resveratrol and oxyresveratrol are naturally occurring phenolic compounds with various bioactivities, but their uses in cosmetics have been partly limited by their chemical instabilities. This study was performed to examine the anti-melanogenic effects of the acetylated derivatives from resveratrol and oxyresveratrol. Resveratrol and oxyresveratrol were chemically modified to triacetyl resveratrol and tetraacetyl oxyresveratrol, respectively. The acetylated compounds were less susceptible than the parent compounds to oxidative discoloration. The acetylated compounds inhibited the activities of tyrosinases less than parent compounds in vitro, but they were as effective at cellular melanogenesis inhibition, indicating bioconversion to parent compounds inside cells. Supporting this notion, the parent compounds were regenerated when the acetylated compounds were digested with cell lysates. Although resveratrol and triacetyl resveratrol inhibited tyrosinase activity less effectively than oxyresveratrol and tetraacetyl oxyresveratrol in vitro, they inhibited cellular melanogenesis more effectively. This discrepancy was explained by strong inhibition of tyrosinase expression by resveratrol and triacetyl resveratrol. Experiments using a reconstituted skin model indicated that resveratrol derivatives can affect melanin synthesis and cell viability to different extents. Collectively, this study suggests that acetylated derivatives of resveratrol have great potential as anti-melanogenic agents for cosmetic use in terms of efficacy, safety, and stability.

Isolation of resveratrol from vitis viniferae caulis and its potent inhibition of human tyrosinase.

Tyrosinase (TYR) catalyzes rate-limiting reactions of cellular melanin synthesis, and its inhibitors are of commercial interest as potential skin whitening agents. However, the limited availability of human TYR makes the screening of TYR inhibitors difficult. To overcome this hurdle, we transformed nonmelanocytic human embryonic kidney (HEK) 293 cells to express human TYR constitutively. Using these cells as a source of human TYR, the ethanolic extracts of 52 medicinal plants grown in Korea were tested for human TYR activity, and the extract of Vitis Viniferae Caulis (dried stems of the grape tree, Vitis vinifera L.) was found to inhibit human TYR activity potently. An active compound was isolated from this extract by solvent fractionation followed by liquid column chromatography and identified as resveratrol by spectroscopic and chromatographic analyses. Resveratrol was determined to be a highly potent inhibitor of human TYR (IC50 = 0.39 µ g mL(-1)) as compared with p-coumaric acid (IC50 = 0.66 µ g mL(-1)) and arbutin (IC50 > 100 µ g mL(-1)) and inhibited melanin synthesis by human epidermal melanocytes at subtoxic concentrations. This study suggests that resveratrol and resveratrol-containing extracts of Vitis Viniferae Caulis have a potential use as skin whitening agents.

p-coumaric acid not only inhibits human tyrosinase activity in vitro but also melanogenesis in cells exposed to UVB.

Tyrosinase (TYR) catalyzes rate-limiting steps of melanogenesis and thus its inhibitors are potentially useful as hypopigmenting agents. Recently, p-coumaric acid (p-CA) has been suggested to interfere with the pro-melanogenic actions of tyrosine due to its structural similarity with tyrosine (An SM et al., Br J Dermatol 2008. 159: 292). In this study, we compared the inhibitory effects of p-CA and two other well known TYR inhibitors used in cosmetics--arbutin and kojic acid--on the catalytic activities of mushroom, murine and human TYRs in vitro, using tyrosine and 3,4-dihydroxyphenylalanine (DOPA) as substrates. The results showed that p-CA is a weaker inhibitor of mushroom TYR but much stronger inhibitor of human or murine TYR in comparison with kojic acid and arbutin. In addition, p-CA inhibited human TYR at much lower concentrations than those required for the inhibition of murine or mushroom TYRs. Enzyme kinetics analysis indicated that p-CA is a mixed type (for tyrosine) or competitive inhibitor (for DOPA) of human TYR. Potent antimelanogenic effects of p-CA were observed in human epidermal melanocytes exposed to UVB. The present study demonstrated that p-CA is a potent and selective inhibitor of human TYR and is potentially useful as a hypopigmenting agent.

Bisabolangelone isolated from Ostericum koreanum inhibits the production of inflammatory mediators by down-regulation of NF-kappaB and ERK MAP kinase activity in LPS-stimulated RAW264.7 cells.

Bisabolangelone, a sesquiterpene derivative, was isolated from the roots of Osterici Radix (Ostericum koreanum Maximowicz). In this study, the anti-inflammatory effect of bisabolangelone was investigated to address potential therapeutic effects in lipopolysaccharide (LPS)-stimulated mouse macrophage RAW 264.7 cells. Bisabolangelone significantly inhibited NO, PGE(2), and pro-inflammatory cytokines by suppressing the mRNA and protein expressions of iNOS and COX-2. Bisabolangelone also inhibited the productions of pro-inflammatory cytokines (TNF-alpha, IL-1beta and IL-6) by suppressing the cytokine mRNA and protein expressions. The molecular mechanism of bisabolangelone-mediated attenuation in RAW 264.7 cells has a close relationship to suppressing the translocation of nuclear factor-kappaB (NF-kappaB) p65 subunit into the nucleus and the phosphorylation of mitogen-activated protein kinases (MAPKs). These results indicate that bisabolangelone inhibits LPS-stimulated inflammation through the blocking of NF-kappaB and MAPK pathways in macrophages, and demonstrated that bisabolangelone possesses anti-inflammatory properties.

Restoration of vitamin C synthesis in transgenic Gulo-/- mice by helper-dependent adenovirus-based expression of gulonolactone oxidase.

Inability to synthesize vitamin C, because of a deficiency in gulonolactone oxidase (GULO) expression, is a genetic deficiency shared by a small number of animals including humans. Although the most overt symptom of vitamin C deficiency, scurvy, can be readily corrected by modest consumption of vitamin C, there is increasing interest in the effect of high-level administration in treating human disease. Using a previously derived Gulo-expressing vector, which produces murine GULO under the control of the murine cytomegalovirus (mCMV) promoter, we constructed and validated a recombinant helper-dependent adenovirus (HDAd-mCMV-Gulo) that can be used to correct this genetic defect. A human liver cell line (Hep G2) infected with the HDAd-mCMV-Gulo vector expressed GULO in a time- and gene dose-dependent manner. These cells also produced ascorbic acid when exogenous gulonolactone was supplemented in the medium. Likewise, Gulo(-/-) mice treated with HDAd-mCMV-Gulo at 2 x 10(11) VP expressed GULO in the liver and produced ascorbic acid. Serum ascorbic acid concentrations in Gulo(-/-) mice injected with GULO-expressing HDAd were elevated to levels comparable to those of wild-type mice (62 +/- 15 microM) after 4 days of infection and were maintained at significantly higher levels compared with those in untreated Gulo(-/-) mice for at least 23 days. A similar elevation was observed in urine and tissue ascorbic acid concentrations in vector-treated animals. In conclusion, we demonstrate here that gene therapeutic HDAd-mCMV-Gulo vectors can mediate the expression of GULO and endogenous production of ascorbic acid in human cells and in Gulo(-/-) transgenic mice. Taken together, these data show that a gene therapy approach can be successfully employed in the treatment and further study of vitamin C deficiency in scurvy-prone mammals.

Flavonoids, taxifolin and luteolin attenuate cellular melanogenesis despite increasing tyrosinase protein levels.

Flavonoids are a group of polyphenolic compounds widely distributed in plants. Their potent bio-activities and relatively low toxicity have rendered them useful ingredients in functional cosmetics. The purpose of the present study was to examine their potential effects on cellular melanogenesis. When tested in murine melanoma B16F10 cells activated by alpha-melanocyte stimulating hormone (alpha-MSH), taxifolin and luteolin inhibited the cellular melanogenesis as effectively as arbutin, one of the most widely used hypopigmenting agents in cosmetics. As opposed to their antimelanogenic effects, taxifolin and luteolin rather increased the tyrosinase protein levels in the absence and presence of alpha-MSH. However, these flavonoids effectively inhibited tyrosinase-catalysed oxidation of l-dihydroxyphenylalanine in cell-free extracts and in living cells. Furthermore, they attenuated cell pigmentation induced by expression of exogenous human tyrosinase. Therefore, the antimelanogenic effects of taxifolin and luteolin are attributed to their inhibitory effects on tyrosinase enzymatic activity, despite their effects on increasing tyrosinase protein levels.

Wen-pi-tang-Hab-Wu-ling-san attenuates kidney fibrosis induced by ischemia/reperfusion in mice.

Renal fibrosis is highly implicated as a cause of chronic renal failure, for which suitable therapeutics have not yet been developed. Recently, it was reported that Wen-pi-tang-Hab-Wu-ling-san (WHW) extract attenuates epithelial cells undergoing mesenchymal transition in cultured Madin-Darby canine kidney cells. This study investigated whether WHW extract prevents renal fibrosis induced by ischemia/reperfusion (I/R) in mice. Ischemia/reperfusion resulted in kidney fibrosis at 14 days after the procedure. When WHW was administered orally to mice beginning from 2 days after the onset of ischemia until killing, the fibrosis was significantly reduced. WHW administration significantly prevented a post-ischemic decrease of copper-zinc superoxide dismutase (CuZnSOD) and manganese superoxide dismutase (MnSOD) activities, leading to decreased lipid peroxidation and hydrogen peroxide production. In addition, WHW administration attenuated the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase 1/2 (JNK1/2) and attenuated the activation of nuclear factor-kappa B (NF-kappaB) in the kidneys subjected to ischemia. In conclusion, WHW extract attenuated the renal fibrosis and the attenuation was associated with a reduction of oxidative stress and an inhibition of ERK1/2, JNK1/2, p38 and NF-kappaB activation. WHW extract may be an attractive agent to attenuate the progression of fibrosis.

Effect of green tea and (-)-epigallocatechin gallate on ethanol-induced toxicity in HepG2 cells.

Despite the continuing reports supporting the hepatoprotective effects of green tea against ethanol intoxication, there remain controversies regarding the active compound(s) and molecular mechanism. These issues were addressed in the present study using cultured HepG2 cells exposed to a lethal dose of ethanol. Gamma-glutamyl transferase (GGT) was chosen as a marker of ethanol toxicity because it is widely used in clinics. When the cells were treated with ethanol at various concentrations, there was a dose-dependent increase of GGT activity in the culture media and loss of cell viability. Pretreatment of the cells with green tea extract attenuated the changes significantly. Among the green tea constituents, (-)-epigallocatechin gallate (EGCG) attenuated the ethanol cytotoxicity effectively, whereas L-theanine and caffeine had no effects. The ethanol cytotoxicity was also attenuated by alcohol dehydrogenase inhibitor 4-methyl pyrazol and GGT inhibitor acivicin as well as by thiol modulators such as S-adenosyl-L-methionine, N-acetyl-L-cysteine and glutathione. EGCG failed to prevent the intracellular glutathione loss caused by ethanol, but it appeared to be a strong GGT inhibitor. Therefore the cytoprotective effects of green tea could be attributed to the inhibition of GGT activity by EGCG. This study suggests that GGT inhibitors including EGCG may provide a novel strategy for attenuating ethanol-induced liver damage.

Wen-Pi-Tang-Hab-Wu-Ling-San extract inhibits the release of inflammatory mediators from LPS-stimulated mouse macrophages.

AIM OF THE STUDY: Wen-Pi-Tang is a traditional herbal prescription that has been used traditionally for the treatment of various inflammatory diseases, including chronic renal failure, renal injury, renal tubular cell damage and diabetic nephropathy. In this study, we investigated the pharmacological activity of modified Wen-Pi-Tang, Wen-Pi-Tang-Hab-Wu-Ling-San (WHW) extract. MATERIALS AND METHODS: Production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6 and NO in supernatant, mRNA expression of TNF-alpha, IL-1beta, IL-6 and iNOS, protein expression of iNOS, phosphorylation of mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-kappa B in the extract were assayed. RESULTS: We found that WHW extract had potent anti-inflammatory effects in LPS-stimulated RAW264.7 cells and primary peritoneal macrophages. WHW extract strongly inhibited the excessive production of inflammatory mediators, nitric oxide (NO), TNF-alpha (TNF-alpha), interleukin 1-beta (IL-1beta) and IL-6 in LPS-stimulated macrophages. The inhibition of inducible nitric oxide synthase (iNOS) and these cytokines resulted from the reduced expressions of mRNAs of iNOS and these cytokines, respectively. WHW extract attenuated the phosphorylation of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinase (JNK), as well as the activation of nuclear factor-kappa B (NF-kappaB) in LPS-stimulated RAW264.7 cells. CONCLUSIONS: These data suggest that WHW extract may exhibit anti-inflammatory effects through the modulation of MAPK and the NF-kappaB-dependent pathway involved in inflammation.

Wen-pi-tang-Hab-Wu-ling-san attenuates kidney ischemia/reperfusion injury in mice. A role for antioxidant enzymes and heat-shock proteins.

The purpose of this study was to investigate the effects of Wen-pi-tang-Hab-Wu-ling-san (WHW) extract, which has been used for treatment of renal diseases, on kidney ischemia/reperfusion (I/R) injury. Thirty minutes of bilateral renal ischemia resulted in disruption of kidney tubular epithelial cells and increased plasma creatinine levels in mice, however these effects were significantly attenuated when WHW was administered prior to I/R. WHW-administration also inhibited post-ischemic decreases of catalase, copper-zinc superoxide dismutase (CuZnSOD), and manganese superoxide dismutase (MnSOD) activity in kidney tissue, leading to decreased tissue hydrogen peroxide levels and lipid peroxidation. Post-ischemic increases of heat-shock protein (HSP)-27 and -72 expressions were greater in mouse kidneys that received WHW. In conclusion, WHW-administration reduced kidney susceptibility to I/R injury, and this reduced susceptibility was associated with greater post-ischemic activation of catalase, CuZnSOD and MnSOD, resulting in reduced hydrogen peroxide levels and lipid peroxidation, as well as higher post-ischemic expression of HSP-27 and -72.

Wen-pi-tang-Hab-Wu-ling-san, an oriental herbal prescription, attenuates epithelial-mesenchymal transdifferentiation stimulated by TGF-beta1 in kidney cells.

Wen-pi-tang-Hab-Wu-ling-san (WHW), an oriental herbal prescription, is currently used in oriental clinics for the treatment of chronic renal failure (CRF). While its effectiveness has been supported by a series of modern studies, the underlying mechanism remains poorly understood. CRF progression involves tubulointerstitial fibrosis where transforming growth factor-beta1 (TGF-beta1) plays a critical role by inducing epithelial-mesenchymal transdifferentiation (EMT). This study examined whether WHW extract attenuated the TGF-beta1-induced EMT in Madin-Darby canine kidney cells. When the cells were stimulated by TGF-beta1 (2.5 ng/mL), they exhibited an elongated, spindle-shaped appearance but this morphological change was significantly suppressed by WHW extract (1 mg/mL). The WHW extract did not show notable cytotoxicity and even mitigated the cytotoxic effects of TGF-beta1. It inhibited the expression of alpha-smooth muscle actin (alpha-SMA), a marker of EMT, but not the secretion of matrix metalloproteinases stimulated by TGF-beta1. The WHW extract also inhibited the phosphorylation of Smad2 that mediates TGF-beta1 signaling leading to alpha-SMA expression. The present study suggests that WHW extract may provide renal protective effects through modulation of the TGF-beta1/Smad2/alpha-SMA pathway involved in fibrosis.