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1.
Antioxidant activity of lactic acid bacteria is associated with multiple health-protective effects. Traditional indexes of chemical antioxidant activities poorly reflect the antioxidant effects of these bacteria in vivo. Cellular antioxidant activity (CAA) assay was used in this study to determine the antioxidant activity of cell-free supernatants (CFSs) of 10 Lactobacillus strains. The performance of the CAA assay was compared with that of four chemical antioxidant activity assays, namely, DPPH radical scavenging, hydroxyl radical scavenging (HRS), reducing power (RP), and inhibition of linoleic acid peroxidation (ILAP). Results of the CAA assay were associated with those of DPPH and ILAP assays, but not with those of RP and HRS assays. The inter- and intra-specific antioxidant activities of CFS were characterized by chemical and CAA assays. L. rhamnosus CCFM 1107 displayed a high antioxidative effect similar to positive control L. rhamnosus GG ATCC 53103 in all of the assays. The CAA assay is a potential method for the detection of antioxidant activities of lactobacilli CFSs.  相似文献   

2.
This study explores the influence of an extract enriched with polyphenol substances obtained from the brown alga Sargassum pallidum and the effect of the Legalon commercial reference preparation on the biochemical indices of the blood at acute hepatic injury induced in rats with carbon tetrachloride (CTC). Administration of S. pallidum extract exhibited a pronounced antioxidant and hepatoprotective effect revealed in reduction of alanine aminotransferase (AlAT) activity in blood plasm, in normalization of superoxide dismutase activity and reduced glutathione contents, of the level of lipid peroxidation, and the liver antiradical activity. We observed recovery of lipid metabolism and elimination of liver fatty infiltration. The S. pallidum extract was as effective as the reference Legalon hepatoprotector and even surpassed it in its ability to restore the phospholipid metabolism. In our opinion, this hepatoprotective effect of S. pallidum extract is associated with the action of polyphenols contained in brown algae, that is, phlorotannins, which are highly active antioxidants and restore the liver metabolic reactions after toxic hepatic injury with CTC.  相似文献   

3.
The present work was aimed at studying the antioxidative activity and hepatoprotective effects of methanolic extract (ME) of Hammada scoparia leaves against ethanol-induced liver injury in male rats. The animals were treated daily with 35 % ethanol solution (4 g?kg?1?day?1) during 4 weeks. This treatment led to an increase in the lipid peroxidation, a decrease in antioxidative enzymes (catalase, superoxide dismutase, and glutathione peroxidase) in liver, and a considerable increase in the serum levels of aspartate and alanine aminotransferase and alkaline phospahatase. However, treatment with ME protects efficiently the hepatic function of alcoholic rats by the considerable decrease in aminotransferase contents in serum of ethanol-treated rats. The glycogen synthase kinase-3 β was inhibited after ME administration, which leads to an enhancement of glutathione peroxidase activity in the liver and a decrease in lipid peroxidation rate by 76 %. These biochemical changes were consistent with histopathological observations, suggesting marked hepatoprotective effect of ME. These results strongly suggest that treatment with methanolic extract normalizes various biochemical parameters and protects the liver against ethanol induced oxidative damage in rats.  相似文献   

4.
Antrodia cinnamomea (A. cinnamomea) is an indigenous medical fungus in Taiwan and has multiple biological functions, including hepatoprotective and immune-modulatory effects. Currently, the commercially available A. cinnamomea are mainly liquid- and solid-state fermented A. cinnamomea. However, the hepatoprotective effect of solid-state fermented A. cinnamomea has never been reported. Here we evaluate the ability of air-dried, ground and non-extracted wheat-based solid-state fermented A. cinnamomea (WFAC) to protect against carbon tetrachloride (CCl4)-induced hepatic injury in vivo. The results showed that oral administration of WFAC dose dependently (180, 540 and 1080 mg/kg) ameliorated the increase in plasma aspartate aminotransferase and alanine aminotransferase levels caused by chronic repeated CCl4 intoxication in rats. WFAC significantly reduced the CCl4-induced increase in hepatic lipid peroxidation levels and hydroxyproline contents, as well as reducing the spleen weight and water content of the liver. WFAC also restored the hepatic soluble protein synthesis and plasma albumin concentration in CCl4-intoxicated rats, but it did not affect the activities of superoxide dismutase, catalase, or glutathione peroxidase. In addition, a hepatic morphological analysis showed that the hepatic fibrosis and necrosis induced by CCl4 were significantly ameliorated by WFAC. Furthermore, the body weights of control rats and WFAC-administered rats were not significantly different, and no adverse effects were observed in WFAC-administered rats. These results indicate that WFAC is a nontoxic hepatoprotective agent against chronic CCl4-induced hepatic injury.  相似文献   

5.
Hypericum ericoides contains quercetin, hyperin, kielcorin and a new flavone, identified as 5,4′- dihydroxy-7-methoxy-6-methylflavone or 6-C-methyl-7-O-methylapigenin.  相似文献   

6.
Rhodiola imbricata is a perennial herb of the family Crassulaceae, which has significant traditional usage as medicine and is also known to biosynthesize phytochemicals such as flavonoids, coumarins and phenyl glycosides. The present investigation was aimed to estimate the hepatoprotective activity of R. imbricata rhizome acetone extract against paracetamol (2 g/kg) induced liver toxicity. Paracetamol was administered to induce hepatic damage in Wistar rats. 200 and 400 mg/kg doses of rhizome acetone extract and silymarin (25 mg/kg) were used as treatment groups. The blood samples were analyzed for biochemical markers of hepatic injury and tissue samples were subjected for estimation of liver antioxidants and histopathological studies. Analysis of the extract treated rats (400 mg/kg) showed an elevation of superoxide dismutase (0.326 units/min/mg protein), catalase (185.03 μmole of H2O2 consumed/min/mg protein), glutothione peroxidase (19.26 mg GSH consumed/min/mg protein) and reduced glutathione (16.2 μmole of GSH/mg protein). Moreover, the biochemical parameters in serum like alkaline phosphatase, serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and lipid profiles were also improved in treated groups compared to the control. The oral administration of different doses of rhizome acetone extract significantly protected the hepatic cells from damage. The hematological and biochemical parameters were also normal in extract treated rats compared to the control and standard (silymarin) groups. The HPLC analysis revealed the presence of some important phenolic compounds which could be responsible for the hepatoprotective activity. This study proved that R. imbricata could be taken as a good natural source of the hepatoprotective agent.  相似文献   

7.
《Life sciences》1994,55(8):PL145-PL150
The effects of the natural flavonoid hispidulin (6-methoxy-5, 7, 4′-trihydroxyflavone) on bromobenzene-induced hepatotoxicity in mice were investigated. We found a correlation between liver injury and hepatic lipid peroxidation besides a strong liver glutathione depletion due to the toxicant. Hispidulin at doses between 50 and 150 mg/kg i.p. compared favourably with the reference compound N-acetyl-L-cysteine for inhibition of liver injury and lipid peroxidation. The flavonoid at the highest dose tested was also able to counteract reduced glutathione depletion induced by bromobenzene in starved mice. These hepatoprotective effects can be related to the antioxidant properties of hispidulin.  相似文献   

8.
Liver damage involves oxidative stress and a progression from chronic hepatitis to hepatocellular carcinoma (HCC). The increased incidence of liver disease in Egypt and other countries in the last decade, coupled with poor prognosis, justify the critical need to introduce alternative chemopreventive agents that may protect against liver damage. The aim of this study was to evaluate the efficacy of exopolysaccharide-peptide (PSP) complex extracted from Pleurotus ostreatus as a hepatoprotective agent against diethylnitrosamine (DEN)/carbon tetrachloride (CCL4)-induced hepatocellular damage in rats. The levels of liver injury markers (ALT, AST and ALP) were substantially increased following DEN/CCl4 treatment. DEN/CCl4 - induced oxidative stress was confirmed by elevated levels of lipid peroxidation and decreased levels of superoxide dismutase, glutathione-S-transferase, and reduced glutathione. PSP reversed these alterations in the liver and serum, and provided protection evidenced by reversal of histopathological changes in the liver. The present study demonstrated that PSP extract from P. ostreatus exhibited hepatoprotective and antioxidant effects against DEN/CCl4-induced hepatocellular damage in rats. Given the high prevalence of HCV-related liver damage in Egypt, our results suggest further clinical evaluation of P. ostreatus extracts and their potential hepatoprotective effects in patients with liver disease.  相似文献   

9.
Yarrow (Achillea millefolium L.) is an important medicinal plant with different pharmaceutical uses. A. millefolium has been used for centuries to treat various diseases including malaria, hepatitis and jaundice. A. millefolium is commonly prescribed to treat liver disorders. It is also used as an anti-inflammatory agent and is a hepatoprotective herb. A. millefolium is considered safe for supplemental use. It has antihepatotoxic effects also. It is prescribed as an astringent agent. It is prescribed in hemorrhoids, headache, bleeding disorders, bruises, cough, influenza, pneumonia, kidney stones, high blood pressure, menstrual disorders, fever, rheumatoid arthritis, gout, osteoarthritis, hemorrhagic disorders, chicken pox, cystitis, diabetes mellitus, indigestion, dyspepsia, eczema, psoriasis and boils.  相似文献   

10.
Matrine is a bioactive component of the traditional Chinese medical herb Sophora flavescens that has been used in China to treat various kinds of diseases including virus hepatitis. However, the molecular mechanisms underlying its hepatoprotective effects remains elusive. In the present study, primary human hepatocytes were employed to elucidate the protective effects and molecular mechanisms of matrine. We observed that low concentrations of matrine had no significant impact on albumin secretion, but high concentrations (>140 mg/L) of matrine decreased the albumin secretion in hepatocytes. Western blot data indicated that matrine at 140 mg/L at 72 h induced protein expression of CYP2A6, CYP2B6 and CYP3A4. Furthermore, high concentrations of matrine reduced LDH and AST levels and were cytotoxic to hepatocytes, leading to a decreased cell viability and total protein amount. Moreover, low concentrations of matrine, enhanced the ECOD activity and decreased the level of NO2 induced by cytokines in human hepatocytes. Taken together, the present study sheds novel light on the molecular mechanisms of matrine and potential application of matrine in hepatic diseases.

Electronic supplementary material

The online version of this article (doi:10.1007/s10616-013-9680-1) contains supplementary material, which is available to authorized users.  相似文献   

11.
Pan M  Yang X  Zhou L  Ge X  Guo X  Liu J  Zhang D  Yang H 《Journal of virology》2012,86(2):1129-1144
Sequence analysis of duck hepatitis virus type 1 (DHV-1) led to its classification as the only member of a new genus, Avihepatovirus, of the family Picornaviridae, and so was renamed duck hepatitis A virus (DHAV). The 5' untranslated region (5' UTR) plays an important role in translation initiation and RNA synthesis of the picornavirus. Here, we provide evidence that the 651-nucleotide (nt)-long 5' UTR of DHAV genome contains an internal ribosome entry site (IRES) element that functions efficiently in vitro and within BHK cells. Comparative sequence analysis showed that the 3' part of the DHAV 5' UTR is similar to the porcine teschovirus 1 (PTV-1) IRES in sequence and predicted secondary structure. Further mutational analyses of the predicted domain IIId, domain IIIe, and pseudoknot structure at the 3' end of the DHAV IRES support our predicted secondary structure. However, unlike the case for the PTV-1 IRES element, analysis of various deletion mutants demonstrated that the optimally functional DHAV IRES element with a size of approximately 420 nt is larger than that of PTV-1 and contains other peripheral domains (Id and Ie) that do not exist within the type IV IRES elements. The domain Ie, however, could be removed without significant loss of activity. Surprisingly, like the hepatitis A virus (HAV) IRES element, the activity of DHAV IRES could be eliminated by expression of enterovirus 2A protease. These findings indicate that the DHAV IRES shares common features with type IV picornavirus IRES elements, whereas it exhibits significant differences from type IV IRESs. Therefore, we propose that DHAV possesses a distinct type IV IRES element of picornavirus.  相似文献   

12.
‘Mandur bhasma’, an ayurvedic preparation of iron is used in traditional medicine against hepatitis. In the present study the hepatoprotective property of this drug was tested in albino rats during CC14 induced hepatic injury. The effect of mandur bhasma on the activities of the lipolytic enzymes of rat liver, kidney and adipose tissue were studied during hepatitis induced by CCl4. The activities of acid lipase, alkaline lipase, lipoprotein lipase and hormone sensitive lipase exhibited significant alterations during CCl4 induced hepatic injury, indicating a role for these enzymes in the mobilization of fat from adipose tissue and accumulation of fat in liver and kidney. Simultaneous treatment with mandur bhasma prevented the paraffin mediated and CC14 mediated changes in the enzyme activities. These results suggest the hepatoprotective role of mandur bhasma during CCl4 induced hepatic injury.  相似文献   

13.
Deoxyelephantopin (DET) is an abundant sesquiterpene lactone isolated from an anecdotally hepatoprotective phytomedicine, Elephantopus scaber. Our objective in this study was to provide scientific evidence for the in vivo efficacy and the underlying mechanisms of action of DET in lipopolysaccharide/d-galactosamine (LPS/D-GalN)-induced fulminant hepatitis. We investigated both the protective effect of pretreatment with DET (10 mg/kg body weight, Pre-DET10) prior to administration of LPS/D-GalN and the therapeutic effect of treatment with 10 mg/kg DET (Post-DET10) or the hepatoprotective drug silymarin (Post-SM10) following the administration of LPS/D-GalN. Our data showed that Pre-DET10 prevented LPS/D-GalN-induced infiltration of F4/80 monocytes/macrophages and an increase of nitrotyrosine and cyclooxygenase-2 protein in liver tissues. Further, Post-DET10 and Psot-SM10 treatments protected against liver cell apoptosis. All three treatments suppressed serum aminotransferase activities, tumor necrosis factor-alpha and interleukin-6 levels, and serum and hepatic matrix metalloproteinase-9 activity. The Pre-DET10 or Post-DET10 and Post-SM10 treatments in combination with inhibition of heme oxygenase-1 expression ultimately decreased protection of mice from LPS/D-GalN-induced mortality, with decreased survival from 75% and 62.5% to 50%, respectively. Results obtained from serial liver scintigraphy with 99mTc-diisopropyl iminodiacetic acid (DISIDA) on single-photon emission computed tomography analysis showed that both liver uptake and excretion times of DISIDA were significantly delayed in LPS/D-GalN-treated animals and were effectively recovered by DET and silymarin treatment. This report demonstrates that DET functions in the modulating multiple molecular targets or signaling pathways that counteract inflammation during the progression of fulminant hepatitis and may serve as a novel lead compound for future development of anti-inflammatory or hepatoprotective agents.  相似文献   

14.
AimsKolaviron, a bioflavonoid isolated from the seeds of Garcinia kola has been reported to possess anti-inflammatory, antioxidant, antigenotoxic and hepatoprotective activities in model systems via multiple biochemical mechanisms. The present study investigated the possible molecular mechanisms underlying the hepatoprotective effects of kolaviron.Main methodsBiomarkers of hepatic oxidative injury, histological and immunohistochemical techniques were used. In addition, the protein expression levels of cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) were evaluated by western blotting while DNA-binding activities of nuclear factor kappa B (NF-κB) and activator protein-1 (AP-1) were determined by electrophoretic mobility shift assay.Key findingsKolaviron administered orally at doses of 100 and 200 mg/kg for 7 days significantly lowered the activities of serum transaminases and γ-glutamyl tranferase induced by single intraperitoneal administration of dimethyl nitrosamine (DMN) (20 mg/kg) and preserved the integrity of the hepatocytes. Also, kolaviron at both doses reduced the DMN induced elevated hepatic levels of malondialdehyde and reversed DMN mediated decrease in hepatic glutathione. The hepatoprotective effect of kolaviron was compared to that of curcumin, an established hepatoprotective agent. Kolaviron inhibited the DMN induced expression of COX-2 and iNOS. Immunohistochemical staining of rat liver verified the inhibitory effect of kolaviron on DMN-induced hepatic COX-2 expression. Furthermore, kolaviron abrogated DMN induced binding activity of NF-κB as well as AP-1.SignificanceThe ability of kolaviron to inhibit COX-2 and iNOS expression through down regulation of NF-κB and AP-1 DNA binding activities could be a mechanism for the hepatoprotective properties of kolaviron.  相似文献   

15.
The extract of Salvia officinalis (Common Sage) exhibited inhibitory activity of STAT3 signal after screening of several plants extracts using the STAT3-responsive reporter system. Cirsiliol, luteolin, and carnosol were identified from the methanol extract of Silvia officinalis as inhibitors of STAT3 signaling and the effects of these three compounds on STAT3 protein or growth inhibition on cancer cells was compared. Luteolin at the dose of 90 μM clearly suppressed the phosphorylation of STAT3 induced by IL-6, while carnosol was prone to decrease total STAT3 proteins at high doses (>90 μM). Cirsiliol had almost no effect. Since the three compounds exhibited similar concentration-dependent suppression patterns in the reporter assay except for cirsiliol became plateau beyond 30 μM, these compounds appeared to function as STAT3 inhibitory factors in different ways. The direct anti-proliferative activity of three compounds was examined with or without the anti-cancer drug gefitinib using HepG2 and A549 cells. The anti-proliferative effect of the three compounds was additively enhanced by gefitinib. At the doses of 3.6 μM, statistically significant suppression of proliferation was observed in HepG2 cells only by cirsiliol among the three compounds in the absence of gefitinib but all three compounds were prone to suppress the proliferation of HepG2 cells and A549 cells dose-dependently although cirsiliol showed a modest dose-dependency and this suppression of proliferation was enhanced by the addition of gefitinib. Cirsiliol, a dimethyoxylated flavone, activated the natural killer activity of KHYG-1 cells against erythroleukemia K562 cells like a hexamethoxylated flavone, nobiletin, suggesting that it may also have an indirect anti-cancer potential through activation of NK cells. These results shed light on the putative anti-cancer potential of Salvia officinalis.  相似文献   

16.
There is accumulative evidence that the metabolism of iron and copper is altered in viral hepatic diseases, and these nutrients might have specific roles in their pathogenesis and progress. The aim of present study was to compare the level of copper (Cu) and iron (Fe) in biological samples (serum, urine, and scalp hair) of female patients suffering from different viral hepatitis (A, B, C, D, and E; n?=?253) of age range 31–45 years. For comparative study, 95 healthy females of the same age group residing in the same city were selected. The elements in the biological samples were analyzed by flame atomic absorption spectrophotometry, prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked by using certified reference materials (CRMs) and with those values obtained by conventional wet acid digestion method on same CRMs. The results of this study showed that the mean values of Cu and Fe were higher in sera and scalp hair samples of hepatitis patients than age-matched control subjects, while the difference was significant (p?<?0.001), in the cases of viral hepatitis B and viral hepatitis C as compared to viral hepatitis A, D, and E. The urinary levels of these elements were found higher in the hepatitis patients than in the age-matched healthy controls (p?<?0.05). These results are consistent with literature-reported data, confirming that hepatic iron and copper overload can directly cause lipid peroxidation and eventually hepatic damage.  相似文献   

17.
Przewalskinic acid A is a rare, water-soluble, and highly biologically active ingredient found, thus far, only in the Salvia przewalskii Maxim herb; however, the content in S. przewalskii herb is very low. In order to obtain useful quantities of przewalskinic acid A, the biotransformatin of salvianolic acid B from Salvia miltiorrhiza root (danshen in Chinese) into przewalskinic acid A was studied using a crude enzyme produced from Aspergillus oryzae D30s strain. The crude enzyme from the A. oryzae strain hydrolyzed salvianolic acid B into przewalskinic acid A and danshensu. The preparation afforded 31.3 g przewalskinic acid A (91.0 % purity) and 13.1 g danshensu (95 % purity) from 75 g salvianolic acid B. The preparation of przewalskinic acid A was therefore very successful with a yield of over 86 %, but the yield of danshensu was only 33 %. The product przewalskinic acid A was identified using ultra-performance liquid chromatography–mass spectrometry (UPLC–MS) and NMR.  相似文献   

18.
In the present study, we investigated the hepatoprotective potential of Parinari curatellifolia Planch (Chrysobalanaceae) in experimental rats in order to ascertain the validity of folkloric claims of its effectiveness in the treatment of hepatic-related disorders. Flavonoid extract of P. curatellifolia seed, PCF (10-, 20- or 30 mg/kg body weight) or silymarin (25 mg/kg), dissolved in corn oil, was administered by gavage to experimental animals once daily for 14 consecutive days before liver damage was chemically induced through the administration of acetaminophen (2 g/kg p.o.) on the 14th day. Hepatoprotection was assessed by analyzing liver homogenate and serum for markers of hepatotoxicity – alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (GGT) and lactate dehydrogenase (LDH) activities as well as prothrombin time (PT). Evaluation of biochemical indices of oxidative stress – level of lipid peroxides (LPO), activities of superoxide dismutase (SOD) and catalase, along with histological assessment of hepatic tissue sections were also carried out. Results revealed that all doses of PCF significantly (P < 0.001) and dose dependently prevented acetaminophen-induced increase in serum activities of hepatic enzymes (ALT, AST, GGT, LDH) and PT. Furthermore, PCF (10- and 20 mg/kg) significantly (P < 0.001) reduced lipid peroxidation in liver tissue and restored the activities of the antioxidant enzymes SOD and catalase toward normal levels. Histopathology of the liver tissue showed that PCF mitigated the toxicant-induced hepatocellular necrosis, reduced inflammatory cell infiltration and enhanced hepatocyte regeneration. The results indicated that P. curatellifolia flavonoids demonstrated remarkable hepatoprotective activity in acute liver injury caused by acetaminophen.  相似文献   

19.
《Phytomedicine》2014,21(2):131-140
It is widely known that hepatitis and its complications such as cirrhosis or hepatocellular carcinoma are one of the major health problems of the world especially since no specific treatment is available. In the present study we investigated the hepatoprotective potential of the methanolic extract of the whole plant of Dodonaea viscosa and its ethyl acetate, aqueous, butanol and n-hexane fractions against carbon tetrachloride (CCl4) induced hepatoxicity in rats. Hepatoprotection was assessed in terms of reduction in serum enzymes (ALT, AST, and ALP) that occur after CCl4 injury, and by histopathology and immunohistochemistry. The methanolic extract reduced the serum enzyme level (ALT, AST, and ALP) down to control levels despite CCl4 treatment. It also reduced the CCl4-induced damaged area to 0% as assessed by histopathology. The CD68+ macrophages were also reduced in number around the central vein area by the methanolic extract. These hepatoprotective effects were better than the positive control silymarin. Similar hepatoprotective activities were found with the ethyl acetate, and aqueous fractions of the methanolic extract. The butanol and n-hexane fractions showed elevated levels of ALT, AST and ALP as compared to the positive control silymarin. Histopathology showed ∼30% damage to the liver cells with the butanol and n-hexane fractions which still showed some protective activity compared to the CCl4 treated control. HPLC fingerprinting suggested that hautriwaic acid present in the methanolic extract and its ethyl acetate, and aqueous fractions may be responsible for this hepatoprotective activity of Dodonaea viscosa which was confirmed by in vivo experiments.  相似文献   

20.
《Phytomedicine》2014,21(2):141-147
Cryptotanshinone from Salvia miltiorrhiza Bunge was investigated for hepatoprotective effects in d-galactosamine (GalN)/lipopolysaccharide (LPS)-induced fulminant hepatic failure. Cryptotanshinone (20 or 40 mg/kg) was orally administered 12 and 1 h prior to GalN (700 mg/kg)/LPS (10 μg/kg) injection. The increased mortality and TNF-α levels by GalN/LPS were declined by cryptotanshinone pretreatment. In addition, cryptotanshinone attenuated GalN/LPS-induced apoptosis, characterized by the blockade of caspase-3, -8, and -9 activation, as well as the release of cytochrome c from the mitochondria. In addition, cryptotanshinone significantly suppressed JNK, ERK and p38 phosphorylation induced by GalN/LPS, and phosphorylation of TAK1 as well. Furthermore, cryptotanshinone significantly inhibited the activation of NF-κB and suppressed the production of proinflammatory cytokines. These findings suggested that hepatoprotective effect of cryptotanshinone is likely associated with its anti-apoptotic activity and the down-regulation of MAPKs and NF-κB associated at least in part with suppressing TAK1 phosphorylation.  相似文献   

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