Modulation of the TLR4/MyD88/NF-κB Pathway by Humulus japonicus Extract Protects Against Alcohol-Induced Liver Injury in a Rat Model.

Alcohol induces liver injury related to oxidative stress and inflammatory responses. The purpose of this study was to investigate the hepatoprotective effect of Humulus japonicus extract (HJE) against alcohol-induced liver injury. Furthermore, we investigated the mechanisms of the protective effect of HJE on alcohol-induced liver injury. The pretreatment of HJE decreased the levels of aspartate aminotransferase, alanine aminotransferase, triglyceride, and total cholesterol in the plasma, suppressed the malondialdehyde, myeloperoxidase, and enhanced the activities of superoxide dismutase, glutathione, and catalase. The inhibitory effect of HJE against oxidative stress may be associated with the upregulation of nuclear factor erythroid 2-related factor 2 and its target gene heme oxygenase-1. Moreover, HJE inhibited the pro-inflammatory cytokines (tumor necrosis factor alpha, interleukin-1 beta) by downregulating toll-like receptor 4, myeloid differentiation primary response 88, and nuclear factor kappa B p65. These findings provide evidence for the elucidation of the hepatoprotective mechanisms for HJE.

Polysaccharide-Rich Extract of Phragmites rhizome Attenuates Water Immersion Stress and Forced Swimming Fatigue in Rodent Animal Model.

Our study aimed to investigate the effects of the polysaccharide-rich extract of Phragmites rhizoma (PEP) against water immersion restraint (WIR) stress and forced swimming-induced fatigue. Exposure to WIR stress significantly increased the ulcer index, bleeding score, the weight of the adrenal gland, blood glucose concentrations, total cholesterol, cortisol, and creatine kinase (CK). The weight of the spleen decreased significantly. In addition, myeloperoxidase (MPO) and thiobarbituric acid-reactive substance (TBARS) were significantly upregulated by WIR stress. The antioxidative factors such as glutathione (GSH) and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the stomach were decreased by WIR stress. Alterations induced by WIR stress were effectively reversed by pretreatment with PEP. The swimming endurance capacity of mice was significantly prolonged by the oral administration of PEP. Swimming-induced fatigue significantly reduced the body weight; however, the injection of PEP inhibited the decrease of body weight. The PEP-treated group had significantly lower CK levels in plasma, an indicator of muscle damage. These results indicated that PEP has anti-stress and anti-fatigue effects, which are mediated by suppressing the hyperactivation of the hypothalamus-pituitary-adrenal axis, and antagonism of the oxidative damages induced by WIR stress and prolonged swimming times.

The protective effect of eupatilin on indomethacin-induced cell damage in cultured feline ileal smooth muscle cells: involvement of HO-1 and ERK.

Chronic users of non-steroidal anti-inflammatory drugs frequently develop ulcerative lesions in their intestines. The purpose of the present study was to investigate whether eupatilin, an active ingredient derived from Artemisia plants, prevents this side effect in vitro. Extracts of the whole herb of Artemisia asiatica Nakai have been used in oriental medicine for the treatment of inflammation. As measured by the MTT assay, the treatment of cultured feline ileal smooth muscle cells (ISMCs) with 2.5mM indomethacin for 2h decreased the cell viability to 43%. Pretreatment with eupatilin resulted in dose-dependent inhibition on indomethacin-induced cell damage. This cytoprotective effect of eupatilin required concentrations of more than 150 microM and incubation periods of longer than 16 h. Pretreatment of ISMC with cycloheximide, an inhibitor of protein synthesis, attenuated the cytoprotective effect of eupatilin, suggesting that eupatilin induces proteins that are responsible for the cytoprotection. Heme oxygenase-1 (HO-1), which is known as a cytoprotective enzyme due to its anti-inflammatory actions, is a candidate protein since ZnPP, an HO-1 inhibitor, repressed the protective effect of eupatilin on indomethacin-induced cell damage in a concentration-dependent manner. Western blot analysis revealed that eupatilin-mediated HO-1 induction occurred in a concentration- and time-dependent manner. We also found that PD98059, a MEK (MAPK/ERK kinase) inhibitor, attenuated the eupatilin-induced HO-1 expression and nuclear translocation of transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2). Taken together, the data imply that eupatilin protects ISMC from cell damage caused by indomethacin, and that its cytoprotective action could be attributed to eupatilin-mediated HO-1 induction via ERK and Nrf2 signaling in ISMC.

DA-9601, a standardized extract of Artemisia asiatica, blocks TNF-alpha-induced IL-8 and CCL20 production by inhibiting p38 kinase and NF-kappaB pathways in human gastric epithelial cells.

AIM: To investigate whether, or how, DA-9601, which is a new gastroprotective agent, inhibits TNF-alpha-induced inflammatory signals in gastric epithelial AGS cells. METHODS: Cell viability was determined by MTT assay. IL-8 and CCL20 promoter activities were determined by a luciferase reporter gene assay. NF-kappaB-dependent transcriptional activity was determined by I-kappaB alpha degradation, NF-kappaB p65 nuclear translocation and a luciferase activity assay. IL-8 and CCL20 gene expression and protein secretion were determined by RT-PCR and an enzyme-linked immunosorbent assay (ELISA). Total and phosphorylated forms of mitogen-activated protein kinases (MAPKs) were determined by Western blot. RESULTS: Treatment of AGS cells with DA-9601 reduced TNF-alpha-induced IL-8 and CCL20 promoter activities, as well as their gene expression and protein release. TNF-alpha also induced NF-kappaB-dependent transcriptional activity in AGS cells. In contrast, in cells treated with DA-9601, TNF-alpha-induced NF-kappaB activity was significantly blocked. Although all three MAP kinase family members were phosphorylated in response to TNF-alpha, a selective inhibitor of p38 kinase SB203580 only could inhibit both NF-kappaB-dependent transcriptional activity and IL-8 and CCL20 production, suggesting a potential link between p38 kinase and NF-kappaB-dependent pathways in AGS cells. Interestingly, DA-9601 also selectively inhibited p38 kinase phosphorylation induced by TNF-alpha. CONCLUSION: DA-9601 blocked TNF-alpha-mediated inflammatory signals by potentially modulating the p38 kinase pathway and/or a signal leading to NF-kappaB-dependent pathways in gastric epithelial cells.

Eupatilin inhibits proliferation of ras-transformed human breast epithelial (MCF-10A-ras) cells.

Artemisia asiatica Nakai has been used frequently in traditional Asian medicine for the treatment of inflammation and cancer. Eupatilin (5,7-dihydroxy-3',4', 6-trimethoxy-flavone) was shown to be a pharmacologically active ingredient of A. asiatica. In the present study, we found that expression of cyclin D1, a key protein that regulates G1/S progression, was decreased in MCF-10A-ras cells treated with eupatilin. Downregulation of cyclin D1 expression by eupatilin was accompanied by a reduced expression of c-Jun and the DNA binding activity of the transcription factor AP-l. The expression of p21waf1/Cip1 was also decreased by eupatilin treatment in both protein and the mRNA levels. We concluded that the inhibitory effect of eupatilin on p21waf1/Cip1 expression is likely to be associated with the downregulation of cyclin D1 expression and AP-1 activation, which play an important role in the cell cycle arrest of ras-transformed breast epithelial cells.

Eupatilin, a pharmacologically active flavone derived from Artemisia plants, induces apoptosis in human gastric cancer (AGS) cells.

Extracts of Artemisia asiatica Nakai (Asteraceae) possess anti-inflammatory and antioxidative activities. Eupatilin (5,7-dihydroxy-3',4', 6-trimethoxyflavone), one of the pharmacologically active ingredients derived from A. asiatica was shown to induce apoptosis in human promyelocytic leukemia (HL-60) cells. In the present study, we examined the ability of eupatilin to induce apoptosis in human gastric cancer (AGS) cells. Eupatilin induced the apoptosis of AGS cells as revealed by a decrease in the ratio of pro-apoptotic Bax and anti-apoptotic Bcl-2, as well as the cleavage of caspase-3 and poly(ADP-ribose)polymerase (PARP). The pro-apoptotic effects of eupatilin were further verified by its perturbation of the mitochondrial transmembrane potential (DeltaPsim). In addition, eupatilin treatment led to an elevated expression of p53 and p21. Eupatilin inhibited the activation of ERK1/2 and Akt, which are important components of cell-survival pathways.

Therapeutic effect of DA-9601 on chronic reflux gastritis induced by sodium taurocholate in rats.

AIM: To investigate the therapeutic effects of DA-9601 on sodium taurocholate (TCA)-induced chronic reflux gastritis in SD rats. METHODS: In this study, we have investigated the therapeutic effects of DA-9601 on chronic erosive and atrophic gastritis induced by 6 mo of TCA administration (5 mmol/L in drinking water) in SD rats. RESULTS: Four weeks of DA-9601 administration (0.065%, 0.216% in rat chow), following the withdrawal of TCA treatment, resulted in a significant decrease in total length of erosions in rats in a dose-dependent manner. Furthermore, the indicators of atrophic gastritis, such as reduced mucosal thickness and reduction in the number of parietal cells, were improved by the administration of DA-9601 in a dose-related manner. DA-9601 also attenuated inflammatory cell infiltration and the proliferation of collagenous fiber in the gastric mucosa. The improvement in the reduction of the gastric mucus was observed in the rats receiving a high dose of DA-9601 (0.216%). The therapeutic effect of DA-9601 on experimental chronic erosive gastritis was superior to that of rebamipide (1.08% in rat chow). Biochemical analyses showed increased mucosal prostaglandin E2 and reduced glutathione levels by DA-9601 treatment. CONCLUSION: We suggest that DA-9601 is a promising agent for the treatment of chronic erosive and atrophic gastritis with an etiological factor of bile reflux. Increased mucosal prostaglandin E2 and reduced glutathione by DA-9601 treatment may be therapeutic mechanisms for chronic erosive and atrophic gastritis.

Anti-diabetic effects of DA-11004, a synthetic IDPc inhibitor in high fat high sucrose diet-fed C57BL/6J mice.

DA-11004 is a synthetic, potent NADP-dependent isocitrate dehydrogenase (IDPc) inhibitor where IC50 for IDPc is 1.49 microM. The purpose of this study was to evaluate the effects of DA-11004 on the high fat high sucrose (HF)-induced obesity in male C57BL/6J mice. After completing a 8-week period of experimentation, the mice were sacrificed 1 hr after the last DA-11004 treatment and their blood, liver, and adipose tissues (epididymal and retroperitoneal fat) were collected. There was a significant difference in the pattern of increasing body weight between the HF control and the DA-11004 group. In the DA-11004 (100 mg/kg) treated group the increase in body weight significantly declined and a content of epididymal fat and retroperitoneal fat was also significantly decreased as opposed to the HF control. DA-11004 (100 mg/ kg) inhibited the IDPc activity, and thus, NADPH levels in plasma and the levels of free fatty acid (FFA) or glucose in plasma were less than the levels of the HF control group. In conclusion, DA-11004 inhibited the fatty acid synthesis in adipose tissues via IDPc inhibition, and it decreased the plasma glucose levels and FFA in HF diet-induced obesity of C57BL/6J mice.

The role of ascorbic acid on the redox status and the concentration of malondialdehyde in streptozotocin-induced diabetic rats.

We investigated the role of ascorbic acid on the redox status in streptozotocin-induced diabetic rats. In the plasma of diabetic rats, the ratio of reduced/total ascorbic acid was significantly decreased as compared with normal control. Ascorbic acid supplementation increased the reduced and total ascorbic acid contents as compared with diabetic control. In the rutin-treatment group, reduced and total contents of ascorbic acid were significantly decreased, however, the ratio of reduced/total contents of ascorbic acid had no difference as compared with diabetic rats. In the insulin-treatment group, this ratio is not significantly different as compared with diabetic control. However, in the insulin plus ascorbic acid treatment group, reduced form and the ratio of reduced/total ascorbic acid were significantly increased as compared with diabetic control. In addition, we measured the contents of malondialdehyde (MDA) in the plasma of diabetic rats. The contents of MDA was increased as compared with normal control, however, in insulin-treatment group, the contents of MDA was decreased as compared with diabetic rats. Ascorbic acid had no effects on the increases of MDA in diabetic rats. In conclusion, plasma ascorbic acid level and its reduced/total ratio reflects the status of the oxidative stress in the diabetic rats. Supplement of ascorbic acid did not correct the ratio of the reduced/ total ascorbic acid. However, supplement of insulin and ascorbic acid corrected the ratio of reduced/total ascorbic acid.