Effect of Korean Red Ginseng on metabolic syndrome.

Metabolic syndrome (MS) refers to a clustering of at least three of the following medical conditions: high blood pressure, abdominal obesity, hyperglycemia, low high-density lipoprotein level, and high serum triglycerides. MS is related to a wide range of diseases which includes obesity, diabetes, insulin resistance, cardiovascular disease, dyslipidemia, or non-alcoholic fatty liver disease. There remains an ongoing need for improved treatment strategies for MS. The most important risk factors are dietary pattern, genetics, old age, lack of exercise, disrupted biology, medication usage, and excessive alcohol consumption, but pathophysiology of MS has not been completely identified. Korean Red Ginseng (KRG) refers to steamed/dried ginseng, traditionally associated with beneficial effects such as anti-inflammation, anti-fatigue, anti-obesity, anti-oxidant, and anti-cancer effects. KRG has been often used in traditional medicine to treat multiple metabolic conditions. This paper summarizes the effects of KRG in MS and related diseases such as obesity, cardiovascular disease, insulin resistance, diabetes, dyslipidemia, or non-alcoholic fatty liver disease based on experimental research and clinical studies.

Phytochemical characterization and hepatoprotective effect of active fragment from Adhatoda vasica Nees. against tert-butyl hydroperoxide induced oxidative impairment via activating AMPK/p62/Nrf2 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Adhatoda vasica Nees., which existed in a large; number of Tibetan medicine prescriptions for hepatopathy, used as an adjuvant to treat liver diseases. HYPOTHESIS/PURPOSE: Oxidative stress is the key player in the development and progression of liver pathogenesis. In recent years, research is increasingly being focused on exploitation of the active components from medicinal plants to combat the liver oxidative injury. In our study, we aimed to screen the active principles from A. vasica and clarify whether they could relieve oxidative damage induced by tert-Butyl hydroperoxide (t-BHP) and its potential mechanism via activating AMPK/p62/Nrf2 pathway. MATERIALS AND METHODS: Ultra performance liquid chromatography (UPLC) was adopted for analysis of chemical composition in the extracts. Furthermore, the antioxidant activity of the fractions was evaluated using DPPH, ABTS and reducing power assay. Along with this, the compounds in this fraction with highest antioxidant activity were analyzed using UPLC-MS. Based on this, the condition for extracting flavonoids of this subfraction was optimized via response surface method. CCK-8 assay was used to detect cell viability. Detection kits were used to measure the activity changes of AST, ALT, LDH and CAT as well as MDA and GSH levels induced by t-BHP. Detection of reactive oxygen species (ROS) production was used DCFH-DA probe. DAPI staining and flow cytometry was used to detect cell apoptosis. In terms of the mechanistic studies, the expression of proteins involved in AMPK/p62/Nrf2 pathway was measured using western blotting. RESULTS: Eventually, 70% ethanol extract from leaf of A. vasica was chosen due to its highest active components compared with other extracts. Further, ethyl acetate fraction derived from 70% ethanol extract in A. vasica (AVEA) possess highest ability for scavenging DPPH and ABTS free radicals as well as strongest reducing power than other fractions. Chemical composition analysis showed that AVEA contained 17 compounds, including 1 quinazoline alkaloid, 12 flavonoid-C-glycosides and 4 flavonoid-O-glycosides. In addition, the conditions (ratio of solid-liquid 1:14, the concentration of ethanol 73%, and the temperature 65 °C) were selected to enrich the flavonoids in AVEA. Furthermore, AVEA could attenuate t-BHP induced hepatocyte damage via increasing the cell viability, restoring abnormal the activities of AST, ALT, LDH and CAT as well as the levels of MDA and GSH. ROS fluorescence intensity was reduced by AVEA. Meanwhile, it could inhibit the cell apoptosis of BRL 3 A cells, as evidenced by restoration of cell morphology and decreasing the number of apoptotic cells. Further mechanistic studies indicated AVEA could promote p-AMPK expression to further induce autophagy adaptor-p62 protein expression, which could autophagic degradation of Keap1, leading to Nrf2 release and translocation into nucleus to induce antioxidant genes (HO-1, NQO-1, GCLC and GCLM) expression. CONCLUSION: In our study, AVEA was first to screen as the active fraction in A. vasica with alkaloids and abundant flavones. Moreover, the fraction potentiates its beneficial aspect by displaying the protective role on relieving t-BHP induced oxidative stress and activating AMPK/p62/Nrf2 pathway. AVEA helps maintain the redox homeostasis of hepatic cells and could be considered as an effective candidate against oxidative stress related liver disorders.

Rutin protects t­butyl hydroperoxide-induced oxidative impairment via modulating the Nrf2 and iNOS activity.

BACKGROUND: Rutin (quercetin-3-O-rutinoside), a flavonoid, is predominantly found in the buckwheat, cranberries, mulberry and citrus fruits. It is used as a restorative in the preparation of herbal medicine, multivitamin and known to reduce the fate of heart attack. HYPOTHESIS: We aimed to elucidate whether rutin attenuates oxidative stress and its possible mechanism of action in ameliorating the deleterious effect of t-BHP. We also provide evidence that rutin protects the antioxidant status of erythrocytes and liver via Nrf2 and iNOS pathway from oxidative stress. STUDY DESIGN/METHOD: Human erythrocytes and mice liver were used for the evaluation of rutin's effect against t-BHP induced oxidative stress. The non-enzymatic (GSH, MDA, -CO, -SH) and enzymatic stress markers (SOD, CAT, GPx, GR and GST) were estimated by the colorimetric method. The level of Nrf2, iNOS, liver marker enzymes, triglycerides, cholesterol, HDL-cholesterol, albumin, BUN was measured using ELISA kits. Reactive oxygen species (ROS) was quantified using flow cytometry and fluorometry. RT-PCR was used for the quantification of Nrf2 and iNOS expression levels in the liver tissue of mice. In silico studies were done through receptor-ligand binding interaction. RESULTS: Pre-treatment with the rutin ameliorated the toxic effect of t-BHP by modulating the basal level of GSH, -SH, MDA and -CO significantly (p < 0.01) with respect to untreated control. Rutin also protected the erythrocytes against the t-BHP-induced oxidative stress as evidenced by augmented activity of antioxidant enzymes (CAT, SOD, GPX, GR and GST). Furthermore, at the highest tested concentration (16.3 µM), it protected the morphology of the erythrocytes by decreasing the ROS level (p < 0.01). In addition, the lower MEF values of rutin (0.520 ±â€¯0.005) alone or along with t-BHP (0.630 ±â€¯0.021) indicated its non-toxic and protective behavior. The qPCR analyses revealed that t-BHP potently up-regulates the iNOS and down regulate the Nrf2 expression which was ameliorated with rutin treatment in a dose-dependent manner like silymarin. CONCLUSION: Our findings demonstrate that rutin potentiates its beneficial aspect by displaying a profound role in iNOS-Nrf2 signaling pathway. Accordingly, it may be concluded that the dietary factors wherein rutin is an ingredient could be helpful in the maintenance of the intracellular redox-homeostasis and thus may be effective against oxidative stress related secondary complications.

Hepatoprotective effects of soluble rice protein in primary hepatocytes and in mice.

BACKGROUND: The production of rice-derived by-products has increased owing to the growing use of processed rice products. The objective of this study was to isolate highly purified proteins from a rice by-product, rice syrup meal, and to examine their hepatoprotective effects in vitro and in vivo. RESULTS: Soluble rice protein (SRP70) was obtained via enzymatic processing of rice syrup meal using Termamyl SC and Alcalase. Mass spectrometry analysis showed that SRP70 contained low-molecular-weight (<600 Da) peptides. SRP70 did not affect the viability of rat primary hepatocytes and ameliorated tert-butyl hydroperoxide (t-BHP)-induced cytotoxicity. t-BHP-induced elevations in hepatocyte alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities were reduced by SRP70 in a dose-dependent manner. In addition, t-BHP exposure increased the level of malondialdehyde, a toxic reactive aldehyde, which was dose-dependently decreased by SRP70 treatment. These SRP70-induced decreases in biochemical parameters were also observed in vivo in mice. In particular, SRP70 increased the activities of liver antioxidant enzymes in t-BHP-treated mice, including catalase and glutathione peroxidase, as well as increasing the level of glutathione, an antioxidant peptide. SRP70-mediated activation of antioxidant enzymes was shown to be due to the up-regulation in their gene expressions, while nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase 4 (NOX4), a pro-oxidant enzyme, was down-regulated by SRP70. Hematoxylin and eosin staining also showed that SRP70 protected the liver from histopathological changes induced by t-BHP. CONCLUSION: Taken together, these data showed that SRP70, which is derived from a rice-processing by-product, had hepatoprotective effects in vitro and in vivo.

Antioxidant activity and protective effect of extract of Celosia cristata L. flower on tert-butyl hydroperoxide-induced oxidative hepatotoxicity.

This study was undertaken to evaluate the antioxidant potential and protective effects of Celosia cristata L. (Family: Amaranthaceae) flower (CCF) extracts on tert-butyl-hydroperoxide (t-BHP)-induced oxidative damage in the hepatocytes of Chang cells and rat livers. In vitro, CCF extracts exhibited protective effect through their radical scavenging ability to enhance cell viability, prevent reactive oxygen species (ROS) generation, and inhibit mitochondrial membrane depolarisation in t-BHP-induced hepatotoxicity in Chang cells. In vivo, oral feeding of CCF (100mg and 500mg/kg of body weight) to rats for five consecutive days before a single dose of t-BHP (2mmol/kg, i.p.) showed a significant (p<0.05) protective effect by lowering serum levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT). The extract decreased the hepatic levels of lipid peroxidation (MDA) and serum level of triglyceride (TG) against t-BHP-induced oxidative stress. These results indicate that CCF extract prevented oxidative stress-induced liver injury by enhancing hepatocyte antioxidant abilities.

Chemical constituents from aerial parts of Caryopteris incana and cytoprotective effects in human HepG2 cells.

An ethyl acetate fraction of the aerial parts of Caryopteris incana (Verbenaceae) showed potent cytoprotective effects against damage to HepG2 cells induced by tert-butylhydroperoxide (t-BHP). To search for hepatoprotective components of C. incana, various chromatographic separations of the ethyl acetate soluble fraction of C. incana led to isolation of three phenylpropanoid glycosides, 6‴-O-feruloylincanoside D, 6‴-O-sinapoylincanoside D and caryopteroside, and two iridoid glycosides, incanides A and B, together with 17 known compounds. Structures of these compounds were determined by spectroscopic analyses. The absolute stereochemistry of the caryopteroside was established with the help of circular dichroism data and in comparison with literature data. All isolated substances were determined for their cytoprotective effects against t-BHP-induced toxicity in HepG2 cells. Among the tested compounds, 6'-O-caffeoylacteoside exhibited the most potent cytoprotective activity with an IC50 value of 0.8±0.1 µM against t-BHP-induced toxicity. Structure-activity relationships of the assay results indicated an important role of the catechol moiety in phenylpropanoid, iridoid and flavonoid derivatives in eliciting cytoprotective effects.

Cytotoxic effects of procyanidins from Castanea mollissima Bl. shell on human hepatoma G2 cells in vitro.

Significant cytotoxic effects of procynadins from chestnut (Castanea mollissima Bl.) shell (CSPC) on human hepatoma G2 (HepG2) cells were found in vitro. CSPC could inbibit HepG2 proliferation in a dose-dependent manner (100-400 µg/mL), arrest cell cycle in the G0/G1 phase, induce apoptosis and trigger necrosis of HepG2. Proapoptotic effect of CSPC was evidenced by nuclear condensation, internucleosomal DNA fragmentation. Treatment of HepG2 cells with CSPC caused a loss of mitochondrial membrane potential and stimulated reactive oxidative species (ROS) generation. These results suggested CSPC could trigger apoptosis and necrotic cell death in HepG2 cell, which might be associated with ROS generation through the mitochondria-dependent signaling way.

Antioxidant activity and protective effects of Trapa japonica pericarp extracts against tert-butylhydroperoxide-induced oxidative damage in Chang cells.

In this study, the antioxidant properties of Trapa japonica pericarp extracts were evaluated through several biochemical assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH), alkyl radical scavenging activity, hydroxyl radical scavenging, ferric reducing antioxidant power (FRAP) assay, ABTS radical scavenging activity and oxygen radical absorbance capacity (ORAC). The antioxidant activities were compared with other natural and synthetic antioxidants. The results showed that higher radical scavenging activity and antioxidant capacity in FRAP than those of vitamin C as a positive control. T. japonica pericarp extracts have antioxidant properties through its ability to prevent tert-butylhydroperoxide (t-BHP)-induced toxicity which enhance the cell viability, reduce reactive oxygen species (ROS) production, inhibits of oxidative damage and mitochondria dysfunction in Chang liver cells. Therefore, based on these finding, it seems reasonable to suggest that T. japonica pericarp extracts has the potential to protect liver against t-BHP-induced cell damage and should be considered as a potential functional food.

Anti-inflammatory activity of edible brown alga Eisenia bicyclis and its constituents fucosterol and phlorotannins in LPS-stimulated RAW264.7 macrophages.

Although individual phlorotannins contained in the edible brown algae have been reported to possess strong anti-inflammatory activity, the responsible components of Eisenia bicyclis have yet to be fully studied. Thus, we evaluated their anti-inflammatory activity via inhibition against production of lipopolysaccharide (LPS)-induced nitric oxide (NO) and tert-butylhydroperoxide (t-BHP)-induced reactive oxygen species (ROS), along with suppression against expression of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), in RAW 264.7 cells. The anti-inflammatory activity potential of the methanolic extract and its fractions of E. bicyclis was in the order of dichloromethane>methanol>ethyl acetate>n-butanol. The strong anti-inflammatory dichloromethane fraction was further purified to yield fucosterol. From the ethyl acetate fraction, six known phlorotannins were isolated: phloroglucinol, eckol, dieckol, 7-phloroeckol, phlorofucofuroeckol A and dioxinodehydroeckol. We found that these compounds, at non-toxic concentrations, dose-dependently inhibited LPS-induced NO production. Fucosterol also inhibited t-BHP-induced ROS generation and suppressed the expression of iNOS and COX-2. These results indicate that E. bicyclis and its constituents exhibited anti-inflammatory activity which might attribute to inhibition of NO and ROS generation and suppression of the NF-κB pathway and can therefore be considered as a useful therapeutic and preventive approach to various inflammatory and oxidative stress-related diseases.

Modulatory effect of methanolic extract of Vernonia amygdalina (MEVA) on tert-butyl hydroperoxide-induced erythrocyte haemolysis.

Reactive oxygen species (ROS) have been implicated in the aetiology of several pathological and degenerative diseases. The protective effect of natural products possessing antioxidant properties has played a crucial role in ameliorating these deleterious effects. This study investigated the chemoprotective properties of the methanolic extract of Vernonia amygdalina (MEVA) in an experimental model of tert-butyl hydroperoxide (t-BHP)-induced human erythrocyte lysis in vitro. Haemolysis was induced by incubating erythrocytes with t-BHP (2 and 3 mM) in vitro. Samples of erythrocyte suspensions were removed at different intervals over a 6-h period, and the degree of haemolysis was measured. The anti-haemolytic effect of MEVA at 25-150 µg ml(-1) concentrations on the samples were assessed and compared with Triton X-100. Administration of t-BHP at 2- and 3-mM concentrations significantly (p < 0.05) induced erythrocyte lysis by 37.5% and 31.4%, respectively. The addition of MEVA, however, reduced t-BHP-induced erythrocyte lysis significantly (p < 0.05) by 39.3%, 48.4%, 67.3% and 73.4% at 25, 50, 100 and 150 µg ml(-1) concentrations, respectively. MEVA likewise protected against t-BHP-induced lipid peroxidation significantly (p < 0.05) at 100 and 150 µg ml(-1) by the fourth hour and non-significantly (p > 0.05) at all concentrations by the sixth hour. The reduced glutathione level was, however, increased with the administration of t-BHP, while a delayed addition of MEVA had no protective effect on the t-BHP-induced cell lysis. These findings therefore suggest that MEVA may have protective antioxidant properties, making it suitable for incorporation into food and drug products.