36kDa Glycoprotein isolated from Rhus verniciflua Stokes fruit has a protective activity to glucose/glucose oxidase-induced apoptosis in NIH/3T3 cells

Isolation, structures and biological activities of medicinal glycoproteins from natural resources: A review

In recent years, natural resources have proven to be tremendous sources of glycoproteins. As biological macromolecules, glycoproteins are essential to the growth and development of organisms, and have attracted increasing attention around the world. This review summarized and discussed the development of glycoproteins from natural resources, including isolation methods, purification processes, structural features and biological activities. Generally, the vast majority of glycoproteins can be isolated by hot water extraction followed by purification through gel filtration chromatography. Combined with component analysis, the physicochemical properties of glycoproteins are studied by using several spectroscopic techniques such as ultraviolet-visible (UV-Visible), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR). Moreover, natural glycoproteins possess various remarkable biological activities, including anti-tumor, anti-oxidant, anti-coagulant and anti-microbial activities. The content of this review will provide a theoretical basis for the research on related glycoproteins and give a perspective on the use of these medical resources.

Preparation and availability analysis of glycoprotein from canola meal

The purpose of this study is to examine the possibility of use in various fields such as cosmetics and food industry by extracting, separating, and purifying canola glycoprotein(hreinafter referred to as CNG) and comparing general characteristics and physiological activities with commercially available carrot glycoprotein(hreinafter referred to as CRG). The CNG had a protein content of 13.12%, which is higher than that of common vegetable glycoproteins, and much higher than the CRG of 2.36%. The molecular weight distribution of the CNG was 263-310 Da, which showed a lower molecular weight distribution than the 566-628 Da of the CRG. The total polyphenol content of the CNG was 29.89 mg/g, which was higher than that of the CRG measured at 1.76 mg g^-1. The DPPP radical scavenging activity of CNG and carrot glycoprotein were 10.07 mg mL^-1 and 7.76 mg mL^-1, respectively, indicating that CNG had slightly higher electron donating ability than CRG. Total antioxidant activity of CNG was 26.84 mg AA eq/g and CRG was 10.53 mg AA eq/g.

Antioxidant, Anti-Lung Cancer, and Anti-Bacterial Activities of Toxicodendron vernicifluum

This work tested antioxidant, anti-lung cancer, and antibacterial activities by in vitro, in vivo, and computational experiments for the metabolites extracted from the bark, seed, and stem of Toxicodendron vernicifluum. The results showed that all the extracts significantly scavenged 1,2-diphenyl-1-picrylhydrazyl (DPPH) in a dose-dependent manner. But, the total phenol content (TPC) ranged from 2.12 to 89.25% and total flavonoids content (TFC) ranged from 1.02 to 15.62% in the extracts. The methanolic bark extract (MBE) exhibited higher DPPH scavenging activity than the other extracts, probably due to the higher content of the TPC and TFC present in it. Among the extracts, only the MBE showed anti-lung cancer activity at an acceptable level with a therapeutic index value (22.26) against human lung carcinoma. This was due to the cancer cell death in A549 induced by MBE through reactive oxygen species (ROS) generation, apoptosis, and cell arrest in G1 phase and inhibition of anti-pro-apoptotic protein survivin. Among the extracts, MBE showed significantly higher antibacterial activity as evident through the higher zone of inhibition 13 ± 0.5 mm against methycilin resistant strain of Staphylococcus aureus (MRSA), Salmonila enteria subp. enterica, and P. aeruginosa, 11 ± 0.3 mm against E. coli and 10 ± 0.2 mm against B. cereus. The MBE also showed an excellent antibacterial activity with lower minimal inhibitory concentration (MIC). Particularly, the MBE showed more significant antibacterial activity in MRSA. The in vivo antibacterial activity of the MBE was further tested in C. elegans model. The treatment of the MRSA induced cell disruption, damage and increased mortality of C. elegans as compared to the untreated and MBE treated C. elegans with normal OP50 diet. Moreover, the MBE treatment enhanced the survival of the MRSA infected C. elegans. The compounds, such as 2,3,3-trimethyl-Octane and benzoic from the MBE, metabolized the novel bacterial topoisomerases inhibitor (NBTI) and MRSA related protein (PBP2a). Overall the T. vernicifluum is potentially bioactive as evident by antioxidant, anti-lung cancer, and antibacterial assays. Further studies were targeted on the purification of the novel compounds for the clinical evaluation.

Comparison of antibacterial activity and phenolic constituents of bark, lignum, leaves and fruit of Rhus verniciflua

Rhus verniciflua is commonly known as a lacquer tree in Korea. The bark of R. verniciflua has been used as an immunostimulator in traditional medicine, but also causes allergic dermatitis due to urushiol derivatives. For the development of active natural resources with less toxicity, the antibacterial activity of various parts of R. verniciflua such as bark, lignum, leaves and fruit, together with chemical composition, were investigated. Among the various parts of R. verniciflua, lignum showed the most potent antibacterial activity against fish pathogenic bacteria such as Edwardsiella tarda, Vibrio anguillarum and Streptococcus iniae. Measurement of total phenolic content and flavonoid content clearly showed a high content of phenolic and flavonoids in lignum among the various parts of R. verniciflua. Further analysis showed a close correlation between antibacterial activity and phenolic content. In addition, methyl gallate and fustin, the major constituents of bark and lignum, showed antibacterial activity, which suggested phenolic constituents as active constituents. The content of urushiols, however, was highest in bark, but there was a trace amount in lignum. LC-MS-MS and PCA analysis showed good discrimination with the difference of phenolic composition in various parts of R. verniciflua. Taken together, phenolic compounds are responsible for the antibacterial activity of R. verniciflua. The lignum of R. verniciflua contains high content of phenolic compounds with less urushiols, which suggests efficient antibacterial activity with less toxicity. Therefore, the lignum of R. verniciflua is suggested as a good source for antibacterial material to use against fish bacterial diseases.

Integrating traditional medicine into modern inflammatory diseases care: multitargeting by Rhus verniciflua Stokes

Despite the fact that numerous researches were performed on prevention and treatment of inflammation related diseases, the overall incidence has not changed remarkably. This requires new approaches to overcome inflammation mediated diseases, and thus traditional medicine could be an efficacious source for prevention and treatment of these diseases. In this review, we discuss the contribution of traditional medicine, especially Rhus verniciflua Stokes, to modern medicine against diverse inflammation mediated diseases. Traditionally, this remedy has been used in Eastern Asia for the treatment of gastric problems, hepatic disorders, infectious diseases, and blood disorders. Modern science has provided the scientific basis for the use of Rhus verniciflua Stokes against such disorders and diseases. Various chemical constituents have been identified from this plant, including phenolic acid, and flavonoids. Cell-based studies have exhibited the potential of this as antibacterial, antioxidant, neuroprotective, anti-inflammatory, growth inhibitory, and anticancer activities. Enormous animal studies have shown the potential of this against proinflammatory diseases, neurodegenerative diseases, diabetes, liver diseases, and chemical insults. At the molecular level, this medicinal plant has been shown to modulate diverse cell-signaling pathways. In clinical studies, Rhus verniciflua Stokes has shown efficacy against various cancer patients such as colorectal, gastric, hepatic, renal, pancreatic, and pulmonary cancers. Thus, this remedy is now exhibiting activities in the clinic.

The cytoprotective effect of sulfuretin against tert-butyl hydroperoxide-induced hepatotoxicity through Nrf2/ARE and JNK/ERK MAPK-mediated heme oxygenase-1 expression

Sulfuretin is one of the major flavonoid components in Rhus verniciflua Stokes (Anacardiaceae) isolates. In this study, we investigated the protective effects of sulfuretin against tert-butyl hydroperoxide (t-BHP)-induced oxidative injury. The results indicated that the addition of sulfuretin before t-BHP treatment significantly inhibited cytotoxicity and reactive oxygen species (ROS) production in human liver-derived HepG2 cells. Sulfuretin up-regulated the activity of the antioxidant enzyme heme oxygenase (HO)-1 via nuclear factor E2-related factor 2 (Nrf2) translocation into the nucleus and increased the promoter activity of the antioxidant response element (ARE). Moreover, sulfuretin exposure enhanced the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase 1/2 (ERK1/2), which are members of the mitogen-activated protein kinase (MAPK) family. Furthermore, cell treatment with a JNK inhibitor (SP600125) and ERK inhibitor (PD98059) reduced sulfuretin-induced HO-1 expression and decreased its protective effects. Taken together, these results suggest that the protective effect of sulfuretin against t-BHP-induced oxidative damage in human liver-derived HepG2 cells is attributable to its ability to scavenge ROS and up-regulate the activity of HO-1 through the Nrf2/ARE and JNK/ERK signaling pathways. Therefore, sulfuretin could be advantageous as a bioactive source for the prevention of oxidative injury.

Leaf extract of Rhus verniciflua Stokes protects dopaminergic neuronal cells in a rotenone model of Parkinson's disease

Objectives

The present study investigated the neuroprotective effects of Rhus verniciflua Stokes (RVS) leaf extract on rotenone-induced apoptosis in human dopaminergic cells, SH-SY5Y.

Methods

Cells were pretreated with RVS extract for 1 h then treated with vehicle or rotenone for 24 h. Cell viability, cell cytotoxicity, cell morphology and nuclear morphology were examined by MTT assay, lactate dehydrogenase release assay, phase contrast microscopy and staining with Hoechast 33342, respectively. Reactive oxygen species were measured by 2′7′-dichlorofluorescein diacetate and fragmented DNA was observed by TUNEL assay. Mitochondrial membrane potential was determined by Rhodamine 123. Pro-apoptotic and anti-apoptotic proteins and tyrosine hydroxylase were analysed by Western blotting.

Key findings

Results showed that RVS suppressed rotenone-induced reactive oxygen species generation, cellular injury and apoptotic cell death. RVS also prevented rotenone-mediated changes in Bax/Bcl-2 levels, mitochondrial membrane potential dissipation and Caspase 3 activation. Moreover, RVS pretreatment increased the tyrosine hydroxylase levels in SH-SY5Y cells.

Conclusions

These findings demonstrate that RVS protects SH-SY5Y cells against rotenone-induced injury and suggest that RVS may have potential therapeutic value for neurodegenerative disease associated with oxidative stress.

Butein from Rhus verniciflua protects pancreatic β cells against cytokine-induced toxicity mediated by inhibition of nitric oxide formation

Butein (3,4,2',4'-tetrahydroxychalcone), a plant polyphenol, is a major component in isolate of Rhus verniciflua STOKES (Anacardiaceae). It is shown to exert various potent effects such as antioxidant, antiinflammatory induction of apoptosis among many properties. In this study, we investigated the effect of butein on cytokine-induced β-cell damage. Pre-treatment with butein is shown to increase the viability of cytokine-treated INS-1 cells at concentrations of 15-30 µM. Butein prevented cytokine-mediated cell death, as well as nitric oxide (NO) production, and these effects correlated well with reduced levels of protein expression of the inducible nitric oxide synthase (iNOS). Furthermore, the molecular mechanisms by which butein inhibits iNOS gene expression appeared to be through the inhibition of nuclear factor-κB (NF-κB) translocation. In a second set of experiments, rat islets were used to demonstrate the protective effects of butein and the results were essentially the same as those observed in Beutin pretreated INS-1 cells. Butein prevented cytokine-induced NO production, iNOS expression, and NF-κB translocation and inhibition of glucose-stimulated insulin secretion (GSIS). In conclusion, these results suggest that butein can be used for the prevention of functional β-cell damage and preventing the progression of Type 1 diabetes mellitus (T1DM).

Sulfuretin isolated from heartwood of Rhus verniciflua inhibits LPS-induced inducible nitric oxide synthase, cyclooxygenase-2, and pro-inflammatory cytokines expression via the down-regulation of NF-kappaB in RAW 264.7 murine macrophage cells

It has been reported that Rhusverniciflua exhibits anti-inflammatory, anti-oxidant and anti-cancer activities. However, little is known about biological activity of sulfuretin, a flavonoid isolated from R.verniciflua. In the present study, we investigated the anti-inflammatory effect and the underlying molecular mechanisms of sulfuretin in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Sulfuretin dose-dependently reduced the productions of nitric oxide (NO), prostaglandin E(2) (PGE(2)), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta) induced by LPS. Consistent with these findings, sulfuretin significantly suppressed the LPS-induced expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TNF-alpha, and IL-1 beta. In addition, sulfuretin attenuated LPS-induced DNA binding and the transcriptional activities of nuclear factor-kappa B (NF-kappaB), which was accompanied by a parallel reduction of degradation and phosphorylation of inhibitory kappa B-alpha (I kappaB-alpha) and consequently by decreased nuclear translocation of p65 subunit of NF-kappaB. Furthermore, pretreatment with sulfuretin significantly inhibited the LPS-stimulated activation of I kappaB kinase beta (IKK beta). Taken together, these results suggest that the anti-inflammatory effect of sulfuretin in LPS-treated RAW 264.7 macrophages is associated with the suppression of NF-kappaB transcriptional activity via the inhibitory regulation of IKKbeta phosphorylation.

Anti-inflammatory effects of sulfuretin from Rhus verniciflua Stokes via the induction of heme oxygenase-1 expression in murine macrophages

Rhus verniciflua Stokes (Anacardiaceae) has traditionally been used as an ingredient in East Asian medicines used to treat oxidative damage and cancer. Sulfuretin is one of the major flavonoid components isolated from R. verniciflua. In the present study, we isolated sulfuretin from R. verniciflua and demonstrated that sulfuretin inhibited inducible nitric oxide synthase (iNOS) protein and mRNA expression, reduced iNOS-derived NO, suppressed COX-2 protein and mRNA expression, and reduced COX-derived PGE(2) production in lipopolysaccharide (LPS)-stimulated RAW264.7 and murine peritoneal macrophages. Similarly, sulfuretin reduced tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) production. In addition, sulfuretin suppressed the phosphorylation and degradation of I kappaB-alpha as well as the nuclear translocation of p65 by the stimulation of LPS in RAW264.7 macrophages. Furthermore sulfuretin induced heme oxygenase (HO)-1 expression through nuclear translocation of nuclear factor E2-related factor 2 (Nrf)2 and increased heme oxygenase (HO) activity in RAW264.7 macrophages. The effects of sulfuretin on LPS-induced NO, PGE(2), TNF-alpha, and IL-1 beta production were partially reversed by the HO-1 inhibitor, tin protoporphyrin (SnPP). Therefore, it is suggested that sulfuretin-induced HO-1 expression plays a role of the resulting anti-inflammatory effects in macrophages. This indicated that the anti-inflammatory effects of sulfuretin in macrophages might be exerted through a novel mechanism that involves HO-1 expression.

Glycoprotein isolated from Cudrania tricuspidata Bureau inhibits iNO and COX-2 expression through modulation of NF-κB in LPS-stimulated RAW 264.7cells

Glycoprotein of Cudrania tricuspidata Bureau (CTB glycoprotein) was isolated from CTB fruits which have been used to heal various disorders of the injury and lung as an herbal agent in Korea since long time ago. The CTB glycoprotein was identified to have a molecular weight of 75kDa and consists of carbohydrate (72.5%) and protein moiety (27.5%). To know inhibitory ability of CTB glycoprotein for inflammation mediated by reactive oxygen radicals, firstly we tested about anti-oxidative activity (DPPH, superoxide anion, and hydroxyl radicals) in cell-free system, and then evaluated changes of inflammation-related signals [intracellular reactive oxygen species (iROS), nitric oxide (NO), nuclear factor-kappa B (NF-κB), COX-2, and iNOS] in the LPS (1μg/ml)-treated RAW 264.7cells. The results in this study showed that CTB glycoprotein (100μg/ml) has a strong scavenging activity against DPPH, superoxide anion, and hydroxyl radicals without any pro-oxidant activity in vitro. In the inflammation-related signals, expression of iROS, NO, NF-κB, COX-2, and iNOS were inhibited by treatment with CTB glycoprotein (50μg/ml) in the presence of LPS (1μg/ml). Taken together, our data obtained from these experiments indicated that CTB glycoprotein suppresses expression of the inflammatory-related proteins (iNOS and COX-2) through regulation of NF-κB. Thus, we speculate that CTB glycoprotein may have therapeutic potential for inflammation-associated disorders.

Effect of gallic acid on high fat diet-induced dyslipidaemia, hepatosteatosis and oxidative stress in rats

Gallic acid (GA) is a naturally abundant plant phenolic compound in the human diet and is known to reduce the risk of disease. In this study, the anti-obesity effect of GA in an animal model of diet-induced obesity was investigated. Obesity was induced in male Wistar rats by feeding them a high-fat diet (HFD). GA was given as a supplement at the levels of 50 and 100 mg/kg rat for a period of 10 weeks. The results showed that the body weight, organ weight of the liver and adipose tissue weights of peritoneal and epididymal tissues in the HFD+GA groups were significantly decreased as compared with the HFD group. Serum TAG, phospholipid, total cholesterol, LDL-cholesterol, insulin and leptin levels in the HFD+GA groups were significantly decreased as compared with the HFD group. Histological study showed that the lipid droplets of rats with HFD+GA diets were significantly smaller than those with HFD diets. Hepatic TAG and cholesterol levels in HFD+GA groups were significantly decreased as compared with the HFD group. Moreover, the consumption of GA reduced oxidative stress and GSSG content and enhanced the levels of glutathione, GSH peroxidase, GSH reductase and GSH S-transferase in the hepatic tissue of rats with HFD-induced obesity. These results demonstrate that intake of GA can be beneficial for the suppression of HFD-induced dyslipidaemia, hepatosteatosis and oxidative stress in rats.

Glycoprotein isolated from Rhus verniciflua Stokes inhibits inflammation-related protein and nitric oxide production in LPS-stimulated RAW 264.7 cells

Rhus verniciflua Stokes (RVS) has traditionally been used for medical purpose, such as healing of inflammatory diseases in South Korea. Glycoprotein (36 kDa) was isolated from RVS fruit, purified and used to evaluate the inhibitory effect on inflammatory-related proteins and nitric oxide (NO) production in lipopolysaccharide (LPS, 200 ng/ml)-stimulated RAW 264.7 (murine macrophage cell line). Our results were showed that RVS glycoprotein has a strong antioxidative activity against lipid peroxyl radicals in cell-free system, and inhibits NO production in LPS-stimulated RAW 264.7 cells. To elucidate the inhibitory effect of RVS glycoprotein on activities of inflammatory-related proteins, we firstly evaluated the amount of intracellular reactive oxygen species (ROS), and expression of intracellular protein kinase C (PKC), nuclear factor (NF)-kappaB, and activator protein-1 (AP-1). The results in the present study showed that RVS glycoprotein (200 microg/ml) inhibits ROS production and PKCalpha translocation, and down-regulates the expression of NF-kappaB and AP-1. Such upstream signals consequently inhibited the levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 expression. Therefore, we speculate that RVS glycoprotein inhibits the inflammatory-related protein and can act as an anti-inflammatory agent.

Rhus verniciflua Stokes glycoprotein (36kDa) has protective activity on carbon tetrachloride-induced liver injury in mice

This study was carried out to investigate the hepatoprotective effect of the glycoprotein isolated from Rhus verniciflua Stokes (RVS), which has traditionally been used for healing of inflammatory diseases. We evaluated the activities of alanine aminotransferase (ALT), lactate dehydrogenase (LDH), thiobarbituric acid-reactive substances (TBARS), and antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)] activities in treatment with carbon tetrachloride (CCl(4)) in vivo. When mice were treated with CCl(4) in the absence of RVS glycoprotein, the activities of ALT, LDH, and TBARS were increased, while the antioxidant enzymes activities were decreased. However, when the mice were treated with CCl(4) in the presence of RVS glycoprotein, the activities of ALT, LDH, and TBARS were significantly reduced and SOD, CAT, and GPx activities were remarkably increased. In addition, RVS glycoprotein increased the nitric oxide (NO) production and decreased the nuclear factor-kappa B (NF-κB) and activator protein-1 (AP-1) activation in CCl(4)-treated mice. Collectively, these results pointed out that RVS glycoprotein can inhibit lipid peroxidation, enhance the activities of antioxidant enzymes, increase the NO production, and decrease the NF-κB and AP-1 activations. Therefore, we speculate that RVS glycoprotein protects from liver damage through its radical scavenging ability.

Anti-platelet effects of bioactive compounds isolated from the bark of Rhus verniciflua Stokes

It has previously been shown that EtOAc extracts of Rhus verniciflua Stokes (RVS) inhibit the platelet aggregation response. In this report, bioassay-guided fractionation using ADP-, arachidonic acid-, and collagen-induced human platelet aggregation by a whole blood aggregometer yielded the bioactive compounds isomaltol and pentagalloyl glucose from different highly effective fractions. In addition, column chromatography of fractions from RVS yielded another five compounds: butin, fisetin, sulfuretin, butein and 3,4',7,8-tetrahydroxyflavone. We investigated the effects of bioactive compounds from RVS fractions on several markers of platelet activation using receptor expression on platelet membranes, including glycoprotein IIb/IIIa (CD41), GPIIb/IIIa-like expression (PAC-1) and P-selectin (CD62), and intracelluar calcium mobilization responses by flow cytometry in healthy subjects. Dose-dependent inhibition of platelet aggregation and significantly decreased platelet activation were observed for the isomaltol- and pentagalloyl glucose-treated platelets, respectively. These results show that isomaltol and pentagalloyl glucose from the bark of Rhus verniciflua Stokes have potent anti-platelet activity and emphasize the need to further examine the mechanism of these active compounds for platelet modulation.