Antifibrotic effects of CGX, a traditional herbal formula, and its mechanisms in rats

Anti-Melanogenic Effects of Fractioned Cynanchum atratum by Regulation of cAMP/MITF Pathway in a UVB-Stimulated Mice Model

Based on traditional pharmacological applications and partial in vitro data, Cynanchum atratum (CA) is proposed to act on skin whitening. However, its functional evaluation and underlying mechanisms have yet to be identified. This study aimed to examine the anti-melanogenesis activity of CA fraction B (CAFB) on UVB-induced skin hyperpigmentation. Forty C57BL/6j mice were exposed to UVB (100 mJ/cm², five times/week) for eight weeks. After irradiation, CAFB was applied to the left ear once a day for 8 weeks (the right ear served as an internal control). The results showed that CAFB significantly reduced melanin production in the ear skin, as indicated by the gray value and Mexameter melanin index. In addition, CAFB treatment notably decreased melanin production in α-MSH-stimulated B16F10 melanocytes, along with a significant reduction in tyrosinase activity. Cellular cAMP (cyclic adenosine monophosphate), MITF (microphthalmia-associated transcription factor), and tyrosinase-related protein 1 (TRP1) were also noticeably downregulated by CAFB. In conclusion, CAFB is a promising ingredient for treating skin disorders caused by the overproduction of melanin and its underlying mechanisms involving the modulation of tyrosinase, mainly mediated by the regulation of the cAMP cascade and MITF pathway.

Comparative Analysis of the Antioxidative and Hepatoprotective Activities of Dimethyl Diphenyl Bicarboxylate in Four Animal Models of Hepatic Injury

As a well-known hepatoprotective and antioxidant agent, dimethyl diphenyl bicarboxylate (DDB) has frequently been employed to remedy various liver diseases. However, it is still uncertain whether DDB exerts consistent hepatoprotective and antioxidative activities against varying degrees of hepatic damage. Therefore, DDB (100, 25, 5, or 50 mg/kg depending on the model) was administered to animals in four representative models of liver injury (CCl₄ chemical acute model, DMN subchronic model, TAA chronic model, and restraint stress psychological acute model). Horizontal comparative analysis indicated that DDB significantly lowered the excess serum AST and ALT levels in the CCl₄ and DMN models but not in the TAA and restraint stress models. In accordance with this result, DDB markedly reduced oxidative stress indices (hepatic MDA and ROS) but restored five main antioxidant components (GSH content, GSH-peroxidase, GSH-reductase, SOD, and catalase activity) in the CCl₄ and DMN models. DDB failed to normalize oxidative stressors in the restraint stress-induced injury model and restore these five antioxidant components in the TAA model. Overall, our results produced a comprehensive overview of the effects of DDB on oxidative stressors and the main antioxidative components using four animal models. These findings will provide valuable clues to guide therapeutic clinical applications.

A Herbal Formula, CGXII, Exerts Antihepatofibrotic Effect in Dimethylnitrosamine-Induced SD Rat Model

We aimed to evaluate the antihepatofibrotic effects of CGXII, an aqueous extract which is composed of A. iwayomogi, A. xanthioides, and S. miltiorrhiza, against dimethylnitrosamine- (DMN-) induced hepatofibrosis. Male Sprague Dawley rats were intraperitoneally injected with 10 mg/kg of DMN for 4 weeks (three consecutive days weekly). Rats were orally given distilled water, CGXII (50 or 100 mg/kg), or dimethyl dimethoxy biphenyl dicarboxylate (50 mg/kg) daily. DMN injection caused substantial alteration of total body weight and liver and spleen mass, whereas they were notably normalized by CGXII. CGXII treatment also markedly attenuated the elevation of serum aspartate aminotransferase and alanine aminotransferase levels, hepatic lipid peroxidation, and protein carbonyl contents. Collagen accumulation in hepatic tissue evidenced by histopathological analysis and quantitative assessment of hepatic hydroxyproline was ameliorated by CGXII. Immunohistochemistry analysis revealed decreased α-smooth muscle actin supporting the antihepatofibrotic effect of CGXII. The profibrogenic cytokines transforming growth factor-β, platelet-derived growth factor-β, and connective tissue growth factor were increased by DMN injection. Administration of CGXII normalized the protein and gene expression levels of these cytokines. Our findings suggest that CGXII lowers the levels of profibrogenic cytokines and thereby exerts antifibrotic effects.

The Dimethylnitrosamine Induced Liver Fibrosis Model in the Rat

Four to six week old, male Wistar rats were used to produce animal models of liver fibrosis. The process requires four weeks of administration of 10 mg/kg dimethylnitrosamine (DMN), given intraperitoneally for three consecutive days per week. Intraperitoneal injections were performed in the fume hood as DMN is a known hepatoxin and carcinogen. The model has several advantages. Firstly, liver changes can be studied sequentially or at particular stages of interest. Secondly, the stage of liver disease can be monitored by measurement of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzymes. Thirdly, the severity of liver damage at different stages can be confirmed by sacrifice of animals at designated time points, followed by histological examination of Masson's Trichome stained liver tissues. After four weeks of DMN dosing, the typical fibrosis score is 5 to 6 on the Ishak scale. The model can be reproduced consistently and has been widely used to assess the efficacy of potential anti-fibrotic agents.

Hydroxysafflor yellow A suppresses liver fibrosis induced by carbon tetrachloride with high-fat diet by regulating PPAR-γ/p38 MAPK signaling

CONTEXT

One approach to protect against liver fibrosis is the use of herb-derived natural compounds, such as hydroxysafflor yellow A (HSYA). The antifibrosis effect of HYSA against liver fibrosis has been investigated; however, its mechanisms have not yet been entirely revealed.

OBJECTIVES

To study the protective effects of HSYA on liver fibrosis induced by carbon tetrachloride (CCl4) and a high-fat diet (HFD), and to determine the mechanism of action of HSYA.

MATERIALS AND METHODS

CCl4 and HFD were used to mimic liver fibrosis in rats, and serum biochemical indicators were determined. The antifibrosis effects of HSYA were evaluated and its mechanisms were investigated by histopathological analysis, immunohistochemical staining, enzyme-linked immunosorbent assays, real-time-PCR, and western blotting.

RESULTS

HSYA reduced CCl4- and HFD-mediated liver fibrosis and ameliorated serum biochemical indicator, downregulated the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) (0.31 ± 0.03 protein, 0.59 ± 0.02 mRNA) and transformin growth factor-β1 (TGF-β1) (0.81 ± 0.02 protein, 0.58 ± 0.04 mRNA), and upregulated the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) (1.57 ± 0.13 protein, 2.48 ± 0.19 mRNA) and matrix metallopeptidases-2 (MMP-2) (2.31 ± 0.16 protein, 2.79 ± 0.22 mRNA) (p < 0.01, versus model group). These effects were significantly attenuated by PPAR-γ antagonist GW9662 via blocking the phosphorylation of p38 MAPK.

DISCUSSION AND CONCLUSION

These data demonstrate a novel role for HSYA in inhibiting CCl4- and HFD-mediated liver fibrosis, and reveal that PPAR-γ and p38 MAPK signaling play pivotal roles in the prevention of liver fibrosis induced by CCl4 and HFD.

The herbal formula CGX ameliorates the expression of vascular endothelial growth factor in alcoholic liver fibrosis

ETHNOPHARMACOLOGIC RELEVANCE

The Chunggan extract (CGX) is a traditional herbal formula prescribed for patients suffering from various liver diseases, including alcoholic liver disease, in which the mechanism of CGX action remains unclear. This study aimed to investigate the anti-hepatic fibrosis effects of CGX and its underlying mechanisms in alcohol-induced rat livers.

MATERIALS AND METHODS

To elucidate the mechanism of action of CGX, we evaluated gene expression profiles in the livers of rats treated with 30% alcohol and anti-fibrotic doses of CGX of 100 and 200 mg/kg/day at 1 day, and 2 and 4 weeks using microarrays. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF), one of the candidate genes selected in this study, in alcohol-induced rat livers were measured by real-time PCR and enzyme-linked immunosorbent assays, respectively.

RESULTS

We identified 4128 genes as differentially expressed by at least twofold between alcohol-only- and alcohol-CGX-fed rats at various doses and time points, compared to naïve control animals. Twenty-three of these genes were associated with liver fibrosis and oxidative stress based on the GeneCards database, resulting in p<0.05 by ANOVA between the alcohol-only and alcohol-CGX groups. Especially, Vegf was decreased in CGX 200 mg/kg/day-fed rat livers at all time points evaluated, and mRNA and protein levels at the 4-week time point were validated.

CONCLUSION

These gene expression profiles provide a better understanding of the mechanisms underlying the anti-fibrotic effects of CGX. Suppression of VEGF may play a critical role in anti-fibrotic action of CGX in alcoholic liver injury.

Traditional uses, phytochemistry, pharmacology, pharmacokinetics and quality control of Polyporus umbellatus (Pers.) Fries: a review

ETHNOPHARMACOLOGICAL RELEVANCE

Polyporus umbellatus (Pers.) Fries (Polyporaceae, Zhuling ) has been commonly used in medicine for a wide range of ailments related to the edema, scanty urine, vaginal discharge, urinary dysfunction, as well as jaundice and diarrhea.

AIM OF THE REVIEW

The present paper reviewed the traditional uses, propagation, phytochemistry, pharmacology, pharmacokinetics and quality control of Polyporus umbellatus.

MATERIALS AND METHODS

All the available information on Polyporus umbellatus was collected via a library and electronic search (using Web of Science, Pubmed, ScienceDirect, Splinker, Google Scholar, etc.).

RESULTS

Phytochemical studies showed the presence of many valuable secondary metabolites such as steroids, polysaccharides, anthraquinones and nucleosides. Crude extracts and isolated compounds showed a wide spectrum of pharmacological activities including diuretic, nephroprotective, anti-cancer, immuno-enhancing, hepatoprotective, anti-inflammatory and antioxidative activities. The pharmacokinetic studies demonstrated that the ergosterol and ergone had a high distribution and absorption in the plasma and the two main components of Polyporus umbellatus were mainly excreted by faeces. The determination of multiple chemical components was successfully applied to the quality control of Polyporus umbellatus.

CONCLUSIONS

Modern phytochemical, pharmacological and metabonomic investigations showed that the crude extracts and isolated compounds from Polyporus umbellatus possess many kinds of biological functions, especially in the diuretic activities and the treatment of kidney diseases as well as anti-cancer, immuno-enhancing and hepatoprotective activities. The pathways of the distribution, absorption, metabolism and excretion of main steroidal compounds were clarified by pharmacokinetic studies. Most of the pharmacological studies were conducted using crude and poorly characterized extracts of Polyporus umbellatus in animals especially in case of diuretic activities and the treatment of kidney diseases. Thus, more bioactive components especially diuretic compounds should be identified using bioactivity-guided isolation strategies and the possible mechanism of action as well as potential synergistic or antagonistic effects of multi-component mixtures derived from Polyporus umbellatus need to be evaluated integrating pharmacological, pharmacokinetic, bioavailability-centered and physiological approaches. In addition, more experiments including in vitro, in vivo and clinical studies should be encouraged to identify any side effects or toxicity. These achievements will further expand the existing therapeutic potential of Polyporus umbellatus and provide a beneficial support to its future further clinical use in modern medicine.

Chunggan extract (CGX), methionine-and choline-deficient (MCD) diet-induced hepatosteatosis and oxidative stress in C57BL/6 mice

In the present study, we aimed to evaluate the hepatoprotective and antioxidant effects of Chunggan extract (CGX) in an animal model of hepatosteatosis. The C57BL/6N mice were fed either methionine- and choline-sufficient (MCS) diet (n = 10) or a methionine- and choline-deficient (MCD) diet (n = 50) for 4 weeks, and then they were treated orally with CGX (100 or 200 mg/kg), ursodeoxycholic acid (80 mg/kg, as a positive control), or distilled water (DW, MCS diet group, and MCD diet group) for the final 2 weeks (once per day). The MCD diet induced severe hepatic injury with the typical features of hepatosteatosis in both serum and hepatic tissues. CGX treatment significantly attenuated these alterations in the serum levels including triglyceride (TG), aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total bilirubin. Moreover, CGX also efficiently prevented from the hepatic TG accumulation in the hepatic tissue, evidenced by histopathological findings, compared with the MCD diet. In addition, CGX treatment significantly ameliorated the excessive oxidative stress and antioxidant markers in the serum as well as the hepatic levels of reactive oxygen species, the levels of malondialdehyde, the protein carbonyl, and total antioxidant capacity, and the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. In conclusion, our results indicate the experimental relevance of CGX for potential clinical application in patients with hepatosteatotic disorders and a possible mechanism related to its antioxidant properties.

Hepatoprotective effect of Amomum xanthoides against dimethylnitrosamine-induced sub-chronic liver injury in a rat model

CONTEXT

Amomum xanthioides Wall. ex Baker (Zingiberaceae) is a tropical medicinal plant that is commonly utilized in the treatment of digestive system disorders in Asia for a long time.

OBJECTIVE

This study aimed to evaluate the hepatoprotective effect and related mechanisms of A. xanthoides.

MATERIALS AND METHODS

Sub-chronic liver injury was induced by dimethylnitrosamine (DMN, 10 mg/kg, three times per week for 3 weeks, i.p.) in rats. Water extract of A. xanthoides (WAX, 50 and 100 mg/kg) was given once a day for 3 weeks.

RESULTS AND CONCLUSION

WAX (100 mg/kg) significantly attenuated the DMN-induced excessive release of alanine aminotransferase (123.6 IU/L), aspartate aminotransferase (227.9 IU/L), alkaline phosphatase (820.9 IU/L) and total bilirubin (0.50 g/dL) in serum (p < 0.01), and hydroxyproline (30.5 mg/g tissue) and malondialdehyde (MDA) (53.6 μM/g tissue) contents (p < 0.01) in liver tissue. Furthermore, WAX significantly ameliorated the depletion of total antioxidant capacity (2.54 μM/mg tissue), superoxide dismutase (0.30 U/mg tissue), glutathione (2.10 μM/mg tissue) and catalase (605.0 U/mg tissue) activities (p < 0.05 or p < 0.01) in liver tissue. Histopathological and immunohistochemical analyses indicated that WAX markedly reduced inflammation, necrosis, collagen accumulation and activation of hepatic satellite cells in the liver. Our findings demonstrated that A. xanthoides exerts favorable hepatoprotective effects via positive regulation of the antioxidative system.

Alleviation of Dimethylnitrosamine-Induced Liver Injury and Fibrosis by Supplementation of Anabasis articulata Extract in Rats

Anabasis articulata (Forssk) Moq. (Chenopodiaceae) is an herb, grows in Egypt, and used in folk medicine to treat diabetes, fever, and kidney infections. The protective and therapeutic effects of the ethanol extract of A. articulata aerial parts were evaluated against dimethylnitrosamine (DMN)-induced liver fibrosis, compared with the standard drug, silymarin. Hepatic hydroxyproline content, serum transforming growth factor-β1 (TGF-β1), interleukin 10 (IL-10) and fructosamine were measured as liver fibrosis markers. Hepatic malondialdehyde (MDA), nitric oxide (NO), catalase (CAT), glutathione reductase (GR) and glutathione content (GSH) were measured as oxidant/antioxidant markers. Parallel histopathological investigations were also performed. Protective and therapeutic administration of A. articulata (100 mg/kg daily for 4 weeks), markedly prevented DMN-induced loss in body and liver weights. The extract significantly inhibited the elevation of hepatic hydroxyproline, NO and MDA (P < 0.05), as well as serum fructosamine, and TGF-β1 (P < 0.05) induced by DMN while it restored IL-10 to normal level in both protective and therapeutic groups. Furthermore, A. articulata prevented the depletion in CAT, GR, and GSH levels (P ≤ 0.05). In addition, oral administration of A. articulata extract and silymarin to both protective and therapeutic groups reduced the increase in liver function enzyme activities; alanine and aspartate amintransferases, gamma-glutamyl transferase in addition to alkaline phosphatase, and caused significant increase in serum albumin concentration as compared to DMN group. These data corresponded closely with those obtained for the drug silymarin. Histopathological studies confirmed the biochemical data and revealed remarkable improvement in liver architecture. Thus, it could be concluded that, A. articulata extract exhibited in vivo hepatoprotective and therapeutic effects against DMN-induced liver injury and may act as a useful agent in controlling the progression of hepatic fibrosis through reduction of oxidative stress and improving liver function.

CGX, a multiple herbal drug, improves cholestatic liver fibrosis in a bile duct ligation-induced rat model

ETHNOPHARMACOLOGIC RELEVANCE

CGX is a modification of a traditional herbal medicine that has been used for various liver disorders as a meaning of "cleaning the liver". The cholestatic liver disorders become prevalent. BACK GROUND AND AIM: This study aimed to investigate the anti-hepatic fibrosis effects of CGX and its underlying mechanisms in a rat model of bile duct ligation (BDL).

MATERIALS AND METHODS

BDL was conducted in SD rats except shame operation group. The rats were orally administrated with distilled water, CGX (25 or 50 mg/kg) or ursodeoxycholic acid (UDCA, 25 mg/kg) for two weeks. The pharmaceutical effects and mechanisms were analyzed in histopathology, biochemistry, oxidative stress/antioxidant biomarkers and hepatic fibrogenic cytokines levels.

RESULTS

BDL markedly elevated white blood cell (WBC) counts as well as changed subset proportions such as increased neutrophils and decreased lymphocytes in peripheral blood. BDL drastically elevated the serum levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total bilirubin, and hepatic tissue levels of hydroxyproline and malondialdehyde (MDA), while it reduced the total glutathione (GSH) content and the activities of GSH-redox system enzymes such as GSH-peroxidase, GSH-reductase and GSH-S-transferase. These alterations were significantly attenuated by CGX treatment (mainly 50 mg/kg). CGX treatment normalized both the accumulation of collagen in hepatic tissue and the increased levels of profibrogenic cytokine including transforming growth factor-β1 (TGF-β1) and platelet-derived growth factor-BB (PDGF-BB). Moreover, CGX treatment enhanced interferon-gamma (IFN-γ) expression compare to the BDL group at the protein and gene level.

CONCLUSION

These results suggest that CGX exerts anti-hepatofibrotic effect in rat BDL model, and the responsible mechanisms involve the inhibition of hepatic fibrogenic cytokines and oxidative stress.

Artemisia capillaris extract protects against bile duct ligation-induced liver fibrosis in rats

Artemisia capillaris has been widely used as a traditional herbal medicine in the treatment of liver diseases. However, no previous study has investigated whether A. capillaries alone is effective in treating pathological conditions associated with cholestatic liver injury. In the present study, we evaluated the anti-hepatofibrotic effects of A. capillaris (aqueous extract, WAC) in a bile duct ligation (BDL)-induced cholestatic fibrosis model. After BDL, rats were given WAC (25 or 50 mg/kg) or urosodeoxycholic acid (UDCA, 25 mg/kg) orally for 2 weeks (once per day). The serum cholestatic markers, malondialdehyde, and liver hydroxyproline levels were drastically increased in the BDL group, while administering WAC significantly reduced these alterations. Administering WAC also restored the BDL-induced depletion of glutathione content and glutathione peroxidase activity. Cholestatic liver injury and collagen deposition were markedly attenuated by WAC treatment, and these changes were paralleled by the significantly suppressed expression of fibrogenic factors, including hepatic alpha-smooth muscle actin (α-SMA), platelet-derived growth factor (PDGF), and transforming growth factor beta (TGF-β). The beneficial effects of WAC administration are associated with antifibrotic properties via both upregulation of antioxidant activities and downregulation of ECM protein production in the rat BDL model.

Ameliorative effect of silibinin against N-nitrosodimethylamine-induced hepatic fibrosis in rats

The protective effect of silibinin (SBN) against hepatic fibrosis induced by repeated intermittent administration of N-nitrosodimethylamine (DMN) was investigated in rats. Oral administration of SBN recovered body and liver weight loss and reversed the elevation of serum AST, ALT and ALP accompanied by their fall in the liver tissue in DMN-induced fibrotic rats. Severe oxidative stress induced in fibrotic rats was evidenced by two to three fold elevation in MDA and protein carbonyl levels associated with a fall in the activities of SOD and CAT in repeated DMN treatment and this adversity was protected by SBN post-treatment. Further, the fall in the activities of ATPases and increase in the levels of hydroxyproline and collagen observed in the liver tissue of DMN treated rats was prevented and reversed back toward normalcy by SBN post-treatment. Recovery of rat liver tissue against DMN-induced hepatocellular necrosis, inflammatory changes and hepatic fibrosis by SBN treatment is also confirmed by both H & E and Masson's trichrome stained histopathological evaluation of liver tissue. In conclusion, SBN exhibit hepatoprotective, antioxidant, free radical scavenging, membrane stabilizing and anti-fibrotic activity against DMN-induced hepatic fibrosis suggesting that it may be useful as a therapeutic agent toward amelioration of hepatic fibrosis.

Inhibitory effects of Scutellaria baicalensis extract on hepatic stellate cells through inducing G2/M cell cycle arrest and activating ERK-dependent apoptosis via Bax and caspase pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The bioactive components extracted from Scutellaria baicalensis Georgi (SB) have been widely used for anti-cancer, anti-oxidation, anti-inflammation and modulating the immune response.

AIM OF THE STUDY

The purpose of this study is to verify the inhibitory effect and the underlying mechanisms of Scutellaria baicalensis ethanol extract (SBEE) on activated hepatic stellate cells which play a central role in liver fibrogenesis.

MATERIALS AND METHODS

Dimethylnitrosamine (DMN)-administrated rat model was applied to evaluate the anti-fibrotic effect of SBEE in vivo. Flow cytometric analysis and immunoblotting were then used to further investigate the molecular mechanisms by which Scutellaria baicalensis extract induces HSC-T6 cell death.

RESULTS

Hepatic collagen contents and alpha-smooth muscle actin levels were remarkably reduced by treating with SBEE. 100 μg/mL SBEE-induced apoptosis of HSC-T6 cell was characterized with elevated levels of activated caspase-3, poly-(ADP-ribose) polymerase (PARP) cleavage, and release of cytochrome c into the cytosol in a time-dependent manner. A 24h treatment of SBEE induced G(2)/M cell cycle arrest with increased expression of p21 and downregulation of cdc2 and cyclin B1 protein levels. Again, SBEE induced bax expression with concomitant decrease of bcl-2 and upregulated the p53 and MAPK signaling in HSC-T6 cells.

CONCLUSIONS

These findings demonstrated that SBEE could prevent hepatic fibrosis by promoting ERK-p53 pathways which may in turn cause G(2)/M cell cycle arrest and activate caspase system resulting in final apoptosis of HSC-T6 cells.

An herbal fruit, Amomum xanthoides, ameliorates thioacetamide-induced hepatic fibrosis in rat via antioxidative system

AIM OF THE STUDY

Amomum xanthoides is a well-known traditional herbal medicine mainly for diverse digestive system disorders in Asia for a long time. In the present study, we investigate the effects and action mechanism of methanol fraction of Amomum xanthoides (MFAX) on thioacetamide (TAA)-induced liver fibrosis in rat model.

MATERIALS AND METHODS

TAA (200mg/kg, ip on twice a week for 14 weeks) treated rats were orally administered with MFAX (25, 50 or 100mg/kg) once a day from the 7th week until 14th week.

RESULT

Significantly elevated serum bilirubin, liver tissue hydroxyproline and malondialdehyde (MDA) in liver fibrosis were ameliorated by MFAX treatment. Further, MFAX treatment attenuated the reactive oxygen species (ROS) levels and restored glutathione (GSH) content and glutathione-peroxidase (GPx) activity. Histopathological data showed that MFAX treatment inhibited collagen accumulation and activation of hepatocyte stellate cells (HSCs) in the liver tissue. Compared to the TAA group, activation of inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-β), platelet-derived growth factor beta (PDGF-β) mRNAs and the level of pro-fibrotic cytokines PDGF-β and connective tissue growth factor (CTGF) in the liver tissue were attenuated in MFAX treated groups.

CONCLUSION

The above evidences collectively indicate that MFAX is a potential herb which can be used as an anti-hepatofibrotic remedy.

Influence of N-acetylcysteine against dimethylnitrosamine induced hepatotoxicity in rats

This study evaluates the hepatoprotective and antioxidant properties of N-acetylcysteine (NAC) on dimethylnitrosamine (DMN) induced hepatotoxicity in male Wistar albino rats. A single intraperitoneal dose of DMN (5 mg/kg b.w.) caused a significant increase in the levels of the serum marker enzymes (aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glutamyl transpeptidase (γ-GT)) and a subsequent decrease in AST, ALT, ALP and increase in LDH and γ-GT in the liver tissue indicating hepatocellular damage. Elevation in the status of lipid peroxidation, fall in the activities of the enzymic (superoxide dismutase, catalase) and non-enzymic antioxidants (vitamin C, vitamin E) in the liver tissue further confirms oxidative stress and hepatocellular damage induced on DMN administration. Oral administration of NAC (50 mg/kg b.w.) for 7 days significantly prevented the above alterations in the status of the marker enzymes of hepatotoxicity and antioxidant parameters and restored them towards normalcy, which was further substantiated by the histopathological studies of the liver tissue. These results suggest that NAC offers hepatoprotection by ameliorating DMN-induced oxidative stress and hepatotoxicity and this protective effect was attributed to its antioxidant and free radical scavenging properties.

N-acetylcysteine attenuates dimethylnitrosamine induced oxidative stress in rats

Oxidative stress has been implicated in the pathogenesis and progression of various hepatic disorders and hence screening for a good hepatoprotective and antioxidant agent is the need of the hour. The present study was aimed to investigate the hepatoprotective and antioxidant property of N-acetylcysteine (NAC) against dimethylnitrosamine (DMN) induced oxidative stress and hepatocellular damage in male Wistar albino rats. Administration of single dose of DMN (5mg/kg b.w.; i.p.) resulted in significant elevation in the levels of serum aspartate transaminase and alanine transaminase, indicating hepatocellular damage. Oxidative stress induced by DMN treatment was confirmed by an elevation in the status of lipid peroxidation (LPO) and reduction in the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase and in the levels of non-enzymic antioxidants, reduced glutathione, vitamin-C and vitamin-E in the liver tissue. DMN induced oxidative stress and hepatocellular membrane instability was further substantiated by a decline in the status of the membrane bound ATPases in the liver tissue. Post-treatment with NAC (50mg/kg b.w.; p.o.) for 7days effectively protected against the DMN induced insult to liver by preventing the elevation in the status of the serum marker enzymes and LPO, and restoring the activities of both the enzymic and non-enzymic antioxidants and membrane bound ATPases towards normalcy. These results demonstrate that NAC acts as a good hepatoprotective and antioxidant agent in attenuating DMN induced oxidative stress and hepatocellular damage.

A traditional formula, Chunggan extract, attenuates thioacetamide-induced hepatofibrosis via GSH system in rats

Chunggan extract (CGX) is a hepatotherapeutic herbal formula which has been traditionally used for patients suffering from various hepatic disorders. This study aimed to elucidate antifibrotic effect and mechanisms of CGX in thioacetamide (TAA) model. Hepatic fibrosis was induced in 45 Sprague-Dawley rats by TAA (200 mg kg(-1), intraperitoneally [ip]) on twice per week for 12 weeks. CGX (100 or 200 mg kg(-1), per oral [po]) was administrated once a day throughout the experiment. CGX treatment ameliorated serum biomarkers. CGX administration significantly attenuated distortion of histopathologic finding, and accumulation of hydroxyproline and malondialdehyde (MDA). CGX treatment significantly decreased transforming growth factor-beta (TGF-β) concentrations and inactivated hepatic stellate cells (HSCs). CGX treatment drastically restored glutathione (GSH) system, while inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-α) significantly down-regulated in liver tissue. CGX showed antifibrotic effect in thioacetamide-induced chronic liver injury model. Its corresponding mechanisms may be mediated via anti-oxidative stress property sustaining GSH system and inhibition of ROS production.

CGX, a traditional Korean medicine ameliorates concanavalin A-induced acute liver injury

Concanavalin A (Con A)-induced acute liver injury model is well established as a model of T cell-mediated liver injury, in which T cells and NKT cells exert their cytotoxicity towards liver cells. In this study, we investigated the protective effects of CGX, a traditional Korean medicine against Con A-induced liver injury and its underlying mechanisms. After pretreatment with CGX (po, 50, 100 or 200 mg/kg) or distilled water once daily during 7 days, Con A (15 mg/kg) was injected intravenously. Thereafter serum level of AST and ALT, lipid peroxidation and cytokines in the liver tissue, and immune cell population in blood and the spleen were analyzed. CGX treatment reduced serum ALT, AST level in a dose-dependent manner. CGX treatment significantly decreased the lipid peroxidation and glutathione depletion in the liver tissue, and also lowered tissue levels of tumor necrotic factor-α and interferon-γ. CGX treatment attenuated the compositional alteration of Tc, Th, NKT, and B cells in blood as well as in the spleen. These results suggest that CGX has hepatoprotective property against Con A-induced liver injury through antioxidant action and immune regulation.