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1.
In the present study, three kinds of phlorotannins, marine algal polyphenol, were isolated from a brown alga Ecklonia cava, and their inhibitory effect on melanogenesis as well as the protective effect against photo-oxidative stress induced by UV-B radiation was investigated. The effect on melanogenesis was evaluated via the inhibitory effects of tyrosinase and melanin synthesis. Among the phlorotannins, dieckol showed higher effect than that of the other phlorotannins in the both assays; especially the value of dieckol in the tyrosinase inhibition assay was relatively higher than that of a commercial tyrosinase inhibitor (kojic acid). The UV-B protection effect was evaluated via DCFH-DA, MTT, comet assays, and morphological changes in fibroblast. Intracellular ROS induced by UV-B radiation was reduced by the addition of phlorotannins and cell viability was dose-dependently increased. Moreover, dieckol demonstrated strong protective properties against UV-B radiation-induced DNA damage via damaged tail intensity and morphological changes in fibroblast. Hence, these results indicated that dieckol isolated from E. cava has potential whitening effects and prominent protective effects on UV-B radiation-induced cell damages, which might be used in pharmaceutical and cosmeceutical industries.  相似文献   

2.
The antidiabetic therapeutic effect of Ecklonia cava, a brown alga, was investigated using streptozotocin-induced type 1 diabetes mellitus rats and C2C12 myoblasts. The methanol extract of E. cava (ECM), having a strong radical scavenging activity, significantly reduced plasma glucose level and increased insulin concentration in type 1 diabetes mellitus rats. Moreover, the elevation of plasma ALT in diabetic rats was dramatically restored near to normal range by the treatment of ECM, whereas AST level was not meaningfully altered in any group throughout the experiment. The characteristic indications of diabetes, such as polyphagia and polydipsia, were greatly improved by ECM treatment as well. The mechanism of action of ECM appears to be, at least partially, mediated by the activation of both AMP-activated protein kinase/ACC and PI-3 kinase/Akt signal pathways. Taken together, the present results suggest that E. cava has both in vivo and in vitro antidiabetic effects.  相似文献   

3.
Ecklonia cava (EC) is a brown alga that evidences radical scavenging, bactericidal, tyrosinase inhibitory and protease inhibitory activities. However, the antiinflammatory effects in human endothelial cells and its molecular mechanism remain poorly understood. In this study, we attempted to determine whether pretreatment with EC extracts induce a significant inhibition of antiinflammatory activities in lipopolysaccharide (LPS) induced human endothelial cells. We found that each EC extract inhibits LPS induced barrier permeability, expression of cell adhesion molecules, monocytes adhesion, and transendothelial migration to human endothelial cells. Further studies revealed that EC extracts suppress the production of tumor necrosis factor-α (TNF-α) and activation of nuclear factor-kappa B (NF-κB). Particularly, the antiinflammatory effects of ethyl acetate (EtOAc) and butanol (n-BuOH) extracts were better than those of other extracts. Collectively, these results suggest that EC extracts possess barrier integrity activity, inhibitory activity on cell adhesion and migration to endothelial cells by blocking the activation of NF-κB expression and production of TNF-α, thereby endorsing its usefulness as therapy for vascular inflammatory diseases.  相似文献   

4.
The aim of this study was to evaluate the radioprotective effects of diphlorethohydroxycarmalol (DPHC), isolated from the brown algae Ishige okamurae, in mice subjected to gamma irradiation.DPHC significantly decreased the level of radiation-induced intracellular reactive oxygen species in cultured Chinese hamster lung fibroblast (V79-4) cells (p < 0.05), enhanced cell viability that decreased after exposure to γ-rays, and reduced radiation-induced apoptosis in the V79-4 cells.Pretreatment with DPHC (100 mg/kg) in mice prior to irradiation significantly protected the intestinal crypt cells in the jejunum (p < 0.01) and maintained villi height (p < 0.01), compared with those of the vehicle-treated irradiated group. Mice pretreated with DPHC also exhibited dose-dependent increases in the bone marrow cell viability. The dose-reduction factor for gamma irradiation in the DPHC-pretreated mice was 2.05 at 3.5 days after irradiation.These results suggest that DHPC plays a role in protecting cells from irradiation-induced apoptosis, through the scavenging of reactive oxygen species in vitro, and that DPHC significantly protected intestinal progenitor cells and bone marrows cells that were decreased by gamma irradiation in vivo.  相似文献   

5.
Hizikia fusiformis is an edible brown alga that is widely consumed in Korea, Japan, and China and possesses a number of potentially beneficial compounds, including antioxidants and anticoagulants. No reports have investigated potential H. fusiformis protectants against ethanol-induced peptic injury. We extracted a polysaccharide from H. fusiformis (Hf–PS-1) that exhibited protective effects against ethanol-induced peptic injury and related mechanisms in rats. Experimental animals were divided into three groups: control, ethanol-only, and ethanol + Hf–PS-1. The ethanol-only group exhibited decreased levels of total glutathione (GSH) and increased levels of jun N-terminal kinase (JNK) phosphorylation relative to the control group, whereas levels were significantly increased and decreased, respectively, in the ethanol + Hf–PS-1 group. The ethanol-only group also exhibited increased levels of extracellular signal-regulated kinase 1/2 (ERK 1/2) phosphorylation relative to the control group; these levels were not significantly different in the ethanol + Hf–PS-1 group. Hf–PS-1 appeared to reduce ethanol-induced gastric injury. Therefore, we suggest that Hf–PS-1 could protect against ethanol-induced peptic ulcers primarily through a mechanism associated with the inhibition of JNK activation.  相似文献   

6.
The fresh fleshy peduncles of Hovenia dulcis have been used as a food supplement and traditional herbal medicine for the treatment of liver diseases and alcoholic poisoning for more than a millennium. The objectives of the present study, therefore, were to determine the antioxidant activity of polysaccharides from the peduncles of H. dulcis (HDPS) and to evaluate its hepatoprotective effect on acute alcohol-induced liver injury in mice. HDPS, prepared by hot water extraction, ethanol precipitation and treatment of macroporous resin, was found to be non-starch polysaccharide and mainly composed of galactose, arabinose, rhamnose and galacturonic acid. In in vitro antioxidant assay, HDPS exhibited high superoxide radical scavenging activity, strong inhibition effect on lipid peroxidation and a medium ferrous ion-chelating activity. For hepatoprotective activity in vivo, the administration of HDPS significantly decreased the serum levels of alanine aminotransferase and aspartate aminotransferase, significantly decreased the liver level of malondialdehyde and remarkably restored the liver activities of superoxide dismutase and glutathione peroxidase in alcohol-induced liver injury mice. The results suggested that HDPS had a significant protective effect against acute alcohol-induced liver injury possibly via its antioxidant activity to protect biological systems against the oxidative stress.  相似文献   

7.
This study examined the effect of genistein isolated from Hydrocotyle sibthorpioides on chronic alcohol-induced hepatic injury and fibrosis. Rats underwent intragastric administration of alcohol (5.0–9.5 g/kg) once a day for 24 weeks. A subset of rats were also intragastrically treated with genistein (0.5, 1 or 2 mg/kg) once a day. Genistein significantly decreased the plasma alcohol concentration, inhibited the activities of alanine and aspartate aminotransferases and decreased levels of inflammatory mediators, including interleukin 6, tumor necrosis factor-α and myeloperoxidase, via down-regulation of nuclear factor-κB. Moreover, genistein effectively inhibited collagen deposition and reduced pathological tissue damage as determined by hepatic fibrosis biomarkers, such as total hyaluronic acid, laminin, and type III collagen. Mechanistically, studies showed that genistein markedly reduced lipid peroxidation, recruited the anti-oxidative defense system, inhibited CYP2El activity, promoted extracellular matrix degradation by modulating the levels of tissue inhibitor of matrix metalloproteinase-1 and matrix metalloproteinase-2, induced HSC apoptosis by down-regulating B-cell lymphoma 2 mRNA, and inhibited the expression of α-smooth muscle actin and transforming growth factor β1 proteins. In conclusion, genistein exerts a preventative effect to ameliorate developing liver injury and even liver fibrosis induced by chronic alcohol administration in rats.  相似文献   

8.
Brown spider bites cause dermonecrotic lesions and systemic manifestations known as loxoscelism. The Loxosceles intermedia venom contains many active proteins, as phospholipase D. There are reports of increased levels of hepatic transaminases in humans with loxoscelism, but detailed studies about the action of the Loxosceles intermedia venom on the liver functions are lacking. The aim of this study was to investigate the effects of the venom and the dermonecrotic recombinant toxin 1 (LiRecDT1) in the liver of Wistar rats injected subcutaneously with venom (80 μg) or toxin (80 μg). After 6 and 12 h the liver immunofluorescence was positive for venom and toxin. Hepatocytes from the venom group were tumefacted and apoptotic. There was leucocyte infiltration in the portal region combined with a high degree of steatosis in 12 h. In the toxin group the histological alterations were less severe. Plasma levels of alanine aminotransferase, aspartate aminotransferase and γ-glutamyl-transferase were significantly elevated only in the venom group in 6 h. Hepatic metabolism was modified: the venom, but not LiRecDT1, reduced gluconeogenesis and ureagenesis from alanine and glycogen accumulation. These results show that the venom is hepatotoxic and that the dermonecrotic toxin is only partly responsible.  相似文献   

9.
Fatty liver and steatosis induced by alcohol is the earliest and most common response of the liver to alcohol and may be a precursor of more severe forms of liver injury. However, the mechanism of liver injury and deposition of fatty liver due to alcohol is complex. The protective effects of saponins from the root of Platycodon grandiflorum (Changkil saponins: CKS) against ethanol-induced liver injury in an enteral alcohol feeding model was investigated. Male Sprague–Dawley rats were given control diets or ethanol-containing diets enterally for 4 weeks. Treatment with CKS for 2 weeks significantly prevented the alcohol-induced increase in serum alanine aminotransferase and aspartate aminotransferase activities or decrease in serum albumin levels. Alcohol elevated the hepatic triglyceride content and induced cytochrome P450 2E1 (CYP2E1) expression. CKS treatment reduced CYP2E1 expression and hepatic triglyceride accumulation and prevented alcoholic liver steatosis. Chronic alcohol feeding decreased AMP-activated protein kinase-alpha (AMPKα) phosphorylation, which was restored by CKS treatment. Recovery of AMPKα phosphorylation by CKS was also followed by an increase in acetyl-CoA carboxylase phosphorylation. Our study suggests that CKS is a promising agent for preventing or treating human alcoholic fatty liver disease.  相似文献   

10.
Liver disorders are one of the common recent problems affects on the human health. These disorders due to many environmental polluted sources. Many herbal, medicinal and pharmaceutical plants and their extracts are widely studied by many researchers. Silybum marianum got a bright reputation in relieve the liver diseases, and that might be for the potent silymarin mixture. Mechanism of action for silymarin conducted mainly to the antiradical and anticarcinogenic roles. Ethyl acetate (100 mg/kg bw) and ethanol seed extracts for S. marianum (100 mg/kg bw) were tested against the injection (i.p.) by carbon tetrachloride (2 ml/kg bw) the inducer of liver damage. Their activity were compared with standard hepatic drug hepaticum (100 mg/kg bw) for 10 days. Ethanolic extract showed the most significantly decrease in the liver enzymes. For the oxidative experiments, ethyl acetate showed the most increase for glutathione level and the risk factor HDL/LDL significantly. Hepaticum was the most powerful group for the significant decreasing for malondialdehyde and fucosidase activity. Some equal improvements were noticed in the histopathological studies for the protective groups.  相似文献   

11.
The study of chronic hepatic fibrosis has been receiving an escalating attention in the past two decades. The aim of the study was to examine the effects of the water extract of Zizyphus spina-christi (L.) (ZSC) on carbon tetrachloride (CCl4)-induced hepatic fibrosis. ZSC extract was daily administered [alone (ZSC-control group) or along with CCl4 (protected groups)] at 0.125 (low dose), 0.250 (medium dose) and 0.350 (high dose) g/kg b.wt. for 8 weeks. Histo-pathological, biochemical and histology texture analyses revealed that ZSC significantly impede the progression of hepatic fibrosis. ZSC resulted in a significant amelioration of liver injury judged by the reduced activities of serum ALT and AST. Oral administration of ZSC has also restored normal levels of malondialdehyde and retained control activities of endogenous antioxidants such as SOD, CAT and GSH. Furthermore, ZSC reduced the expression of α-smooth muscle actin, the deposition of types I and III collagen in CCl4-injured rats. Texture analysis of microscopic images along with fibrosis index calculation showed improvement in the quality of type I collagen distribution and its quantity after administration of ZSC extract. These results demonstrate that administration of ZSC may be useful in the treatment and prevention of hepatic fibrosis.  相似文献   

12.
Objective:  To evaluate the potential of Azadirachta indica leaf extracts against Salmonella typhimurium-induced inflammation in BALB/c mice. Design:  Qualitative tests of A. indica leaf extracts were conducted for screening of various phytochemicals. The antiinflammatory potential of A. indica leaf extracts on S. typhimurium and its outermembrane proteins (OMPs)-induced inflammation was assessed by hyperalgesic (flicking) response of the mice inflammed paws. The monokines (IL-1α, IL-6 and TNF-α) activities in the culture supernatants of macrophages (infected with bacteria and interacted with OMPs) in the presence or absence of A. indica leaf extracts was assessed by ELISA. Results:  Aqueous and petroleum ether A. indica leaf extracts reduced the inflammation caused by S. typhimurium and its OMPs as assessed by paw flicking response. Petroleum ether A. indica leaf extract was found to be more effective than aqueous A. indica leaf extract. Significantly lower levels of monokines (IL-6 and TNF-α) were also observed in the presence of petroleum ether A. indica leaf extracts than aqueous A. indica leaf extract. These observations may be due to the presence of steroids and triterpenoids observed in petroleum ether extract. Conclusion:  Petroleum ether A. indica leaf extract seems promising to combat S. typhimurium-induced inflammation. Received 6 June 2008; accepted 29 October 2008  相似文献   

13.
The protective effects of Dunaliella salina (D. salina) on liver damage were evaluated by carbon tetrachloride (CCl4)-induced hepatotoxicity in mice. Male ICR mice were orally treated with D. salina or silymairn daily with administration of CCl4 twice a week for 8 weeks. CCl4 induced liver damage and significantly (p < 0.05) increased the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in serum and decreased the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), and GSH content in liver whereas increased hepatic malondialdehyde (MDA) content as compared with control group. Treatment with D. salina or silymarin could significantly (p < 0.05) decrease the ALT, AST, and ALP levels in serum and increase the activities of SOD, catalase, GSH-Px, glutathione reductase, and GSH content and decrease the MDA content in liver when compared with CCl4-treated group. Liver histopathology also showed that D. salina reduced the incidence of liver lesions induced by CCl4. The results suggest that D. salina exhibits potent hepatoprotective effects on CCl4-induced liver damages in mice, and that the hepatoprotective effects of D. salina may be due to both the increase of antioxidant enzymes activities and inhibition of lipid peroxidation.  相似文献   

14.
The protective effects of saponins isolated from the root of Platycodon grandiflorum (Changkil saponins: CKS) against alcoholic steatosis in liver injury induced by acute ethanol administration were investigated. Pretreatment with CKS prior to ethanol administration significantly prevented the increases in serum alanine aminotransferase activity, hepatic TNF-α level, hepatic lipid peroxidation and hepatic triglyceride level. CKS prevented ethanol-induced steatosis and necrosis, as indicated by liver histopathological studies. Additionally, CKS protected against ethanol-induced depletion of hepatic glutathione levels. CYP2E1 has been suggested as a major contributor to ethanol-induced oxidative stress and liver injury. The concurrent administration of CKS efficaciously abrogated the CYP2E1 induction and CYP2E1-dependents hydroxylation of aniline as compared to the individual treatment at higher doses. These findings suggest that CKS may prevent ethanol-induced acute liver injury, possibly through its ability to block CYP2El-mediated ethanol bioactivation and its free radical scavenging effects.  相似文献   

15.
Vetter RS 《Toxicon》2011,58(8):623-625
Many medically important animals exhibit fluctuating seasonal abundance such that risk from envenomation or disease is not constant throughout the year. As indicated by homeowner submissions, brown recluse spiders, Loxosceles reclusa, show seasonal peaks of activity during summer and paucity in winter. This information should be incorporated as part of the diagnostic algorithm for physicians when considering the probability of loxoscelism in endemic Loxosceles areas especially if a skin lesion occurs when spiders are scarce.  相似文献   

16.
The hepatoprotective and antioxidant activity of 50% ethanolic extract of whole plant of Amaranthus spinosus (ASE) was evaluated against carbon tetrachloride (CCl4) induced hepatic damage in rats. The ASE at dose of 100, 200 and 400 mg/kg were administered orally once daily for fourteen days. The substantially elevated serum enzymatic levels of serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (SALP) and total bilirubin were restored towards normalization significantly by the ASE in a dose dependent manner. Higher dose exhibited significant hepatoprotective activity against carbon tetrachloride induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. Meanwhile, in vivo antioxidant activities as malondialdehyde (MDA), hydroperoxides, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were also screened which were also found significantly positive in a dose dependent manner. The results of this study strongly indicate that whole plants of A. spinosus have potent hepatoprotective activity against carbon tetrachloride induced hepatic damage in experimental animals. This study suggests that possible mechanism of this activity may be due to the presence of flavonoids and phenolics compound in the ASE which may be responsible to hepatoprotective activity.  相似文献   

17.
Fumonisin B(1) (FB(1)) is a mycotoxin produced by Fusarium verticillioides found on corn and corn-based foods. It causes equine leukoencephalomalacia, porcine pulmonary edema, and liver and kidney damage in most animal species. Fumonisin B(1) perturbs sphingolipid metabolism by inhibiting ceramide synthase activity, leading to the production of cell signaling factors including tumor necrosis factor alpha (TNF-alpha). The signal pathways of TNF-alpha are important factors in the pathogenesis of FB(1) hepatotoxicity. In the present study, female BALB/c mice were treated daily with 750 mg/kg silymarin by gavage and 2.25 mg/kg FB(1) subcutaneously for 3 days. Then, 1 day after the last FB(1) injection, the mice were euthanized and blood and tissues were sampled for analyses. Silymarin significantly diminished FB(1)-induced elevation of plasma alanine aminotransferase and aspartate aminotransferase activities and the number of apoptotic hepatocytes, while it augmented hepatocyte proliferation indicated by an increase in proliferating cells. Silymarin dramatically potentiated FB(1)-induced accumulation of free sphinganine and sphingosine in both liver and kidney. Silymarin itself slightly increased expression of hepatic TNF-alpha; however, it prevented the FB(1)-induced increases in TNF-alpha, TNF receptor 1, TNF receptor-associated apoptosis-inducing ligand, lymphotoxin beta, and interferon gamma. The induction of transforming growth factor beta1 expression in liver following FB(1) treatment was not affected by silymarin. These findings suggest that silymarin protected against FB(1) liver damage by inhibiting biological functions of free sphingoid bases and increasing cellular regeneration.  相似文献   

18.
This study investigated the protective effect of Emblica officinalis against alcohol-induced biochemical and biophysical changes in rat erythrocyte membranes. Thirty-two male rats were divided into four groups (= 8 in each group): control (C), alcohol (A), alcohol plus Emblica fruit extract (A + EFE) and Emblica fruit extract (EFE) alone. Administration of twenty percent alcohol (5 g/kg body weight) to rats significantly increased cholesterol/phospholipid (C/P) ratio, lipid peroxidation and the activities of Na+/K+ and Mg2+ ATPases in erythrocyte membranes as well as augmented nitric oxide (NO) levels. However, membrane fluidity studies using the fluorescent probe DPH (1,6 diphenyl 1,3 hexatriene) reveals that alcohol administration significantly (p < 0.05) increased membrane anisotropic values and altered membrane individual phospholipid content. Administration of EFE (250 mg/kg body weight) to alcoholic rats resulted in significant (p < 0.05) reduction of NO levels, erythrocyte membrane lipid peroxidation, C/P ratio, activities of Na+/K+ and Mg2+ ATPases and fluorescent anisotropic values. Further, EFE administration to alcoholic rats beneficially modulated membrane properties as evidenced from the contents of total phospholipids as well individual phospholipid classes. The tannoid principles present in Emblica offers protection against alcohol induced adverse effects in rats.  相似文献   

19.
The effects of oral administration of Musa sapientum and Musa suerier on prevention of UVB induced skin damages were investigated in male ICR mice. Animals were orally administered 50 mg/day ascorbic acid, or M. sapientum or M. suerier’s fruit pulps at dose of 0.5, 1 or 1.5 mg/g body weight/day for 12 weeks. Concurrently, the shaved backs of animals were irradiated with UVB for 12 weeks. The intensity of irradiation was progressively increased, from 54 mJ/cm2 per exposure at week 1–126 mJ/cm2 at week 11. A significant decrease (p < 0.05) in skin elasticity (from 0.82 ± 0.02 to 0.42 ± 0.09) and total glutathione (from (193.6 ± 18.7 to 152.7 ± 7.8 ng/mg protein) as compared with the control group (water-administered UVB-irradiated mice) was observed after 12 weeks of UVB exposure. When l-ascorbic acid (0.72 ± 0.01) or 1 mg/g body weight/day M. suerier (0.84 ± 0.06) were administered to UVB-irradiated mice, the reduction in skin elasticity was significantly inhibited (p < 0.05). Moreover, the significant increase (p < 0.05) in level of total glutathione was found in these groups (220.8 ± 13.3 ng/mg protein for l-ascorbic acid and 224.9 ± 20.1 ng/mg protein for M. suerier). These findings suggest the potential effect of daily consumption of M. suerier on prevention of skin damage from repeated UVB exposure.  相似文献   

20.
The study investigated the protective effect of electrolyzed reduced water (ERW) against carbon tetrachloride (CCl4)-induced liver damage. Male ICR mice were randomly divided into control, CCl4, CCl4 + silymarin, and CCl4 + ERW groups. CCl4-induced liver lesions include leukocytes infiltration, hepatocyte necrosis, ballooning degeneration, mitosis, calcification, fibrosis and an increase of serum alanine aminotransferase (ALT), and aminotransferase (AST) activity. In addition, CCl4 also significantly decreased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). By contrast, ERW or silymarin supplement significantly ameliorated the CCl4-induced liver lesions, lowered the serum levels of hepatic enzyme markers (ALT and AST) and increased the activities of SOD, catalase, and GSH-Px in liver. Therefore, the results of this study show that ERW can be proposed to protect the liver against CCl4-induced oxidative damage in mice, and the hepatoprotective effect might be correlated with its antioxidant and free radical scavenging effect.  相似文献   

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