Emerging therapies for liver fibrosis

NAFLD: Mechanisms, Treatments, and Biomarkers

Nonalcoholic fatty liver disease (NAFLD), recently renamed metabolic-associated fatty liver disease (MAFLD), is one of the most common causes of liver diseases worldwide. NAFLD is growing in parallel with the obesity epidemic. No pharmacological treatment is available to treat NAFLD, specifically. The reason might be that NAFLD is a multi-factorial disease with an incomplete understanding of the mechanisms involved, an absence of accurate and inexpensive imaging tools, and lack of adequate non-invasive biomarkers. NAFLD consists of the accumulation of excess lipids in the liver, causing lipotoxicity that might progress to metabolic-associated steatohepatitis (NASH), liver fibrosis, and hepatocellular carcinoma. The mechanisms for the pathogenesis of NAFLD, current interventions in the management of the disease, and the role of sirtuins as potential targets for treatment are discussed here. In addition, the current diagnostic tools, and the role of non-coding RNAs as emerging diagnostic biomarkers are summarized. The availability of non-invasive biomarkers, and accurate and inexpensive non-invasive diagnosis tools are crucial in the detection of the early signs in the progression of NAFLD. This will expedite clinical trials and the validation of the emerging therapeutic treatments.

Quantitative T2 mapping of rats with chronic hepatitis

The aim of the study was to explore the diagnostic value of T2 mapping in an experimental rat model of chronic liver disease. Chronic hepatitis was induced in Sprague-Dawley male rats (n=88) by intraperitoneal and abdominal subcutaneous injection of carbon tetrachloride in olive oil. The normal control rats (n=12) were similarly injected with the same dose of normal saline. All rats were randomly selected and subjected to T2-weighted/spectral adiabatic inversion recovery and multiple gradient- and spin-echo sequence. After scanning, rats were sacrificed immediately and livers removed for staining with hematoxylin and eosin, as well as Masson's trichrome, to determine the pathological stage of hepatic fibrosis, necroinflammatory activity and steatosis. The T2 values were measured and associated with histopathological findings. The T2 values were significantly associated with hepatic fibrosis (P<0.05), but not with hepatitis (P>0.05) or steatosis (P>0.05). By partial correlation analysis, a significant positive correlation was observed between the T2 values and stages of liver fibrosis (r=0.820; P<0.05). T2 values increased with progressive hepatic fibrosis. The differences between T2 values and stages of liver fibrosis were statistically significant. Statistically significant differences were observed between different stages of liver fibrosis (P<0.05), with an area under the curve value of 0.944 for predicting stage F1 or greater, 0.942 for stage F2 or greater, 0.958 for stage F3 or greater, and 0.948 for F4. Thus, the T2 value is one of the quantitative indices of imaging and accurately reflects the stages of liver fibrosis.

Sidr honey abrogates the oxidative stress and downregulates the hyaluronic acid concentration and gene expression of TGF-β1 and COL1a1 in rat model of thioacetamide-induced hepatic fibrosis

Liver fibrosis is a major health concern, which might progress to cirrhosis. To date, treatment trials rely mainly on the removal of the causative factor. The current study investigated the potential ameliorative role of sidr honey on thioacetamide (TAA)-induced liver fibrosis in rats. Forty-eight Wistar albino rats were equally allocated into four groups: control; sidr honey (5g/kg body weight (BW), orally); TAA (200 mg/kg BW, IP three times weekly/15 weeks); and sidr honey plus TAA at the same dose and administration rout. Rats co-treated with sidr honey plus TAA revealed significant reduction in hepatic malondialdehyde, hyaluronic acid (HA), alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, direct bilirubin, and hepatic mRNA expression of transforming growth factor (TGF)-β1 and collagen type I alpha 1 chain (COL1a1) compared to TAA-exposed rats. In addition, the hepatoprotective potential of sidr honey was indicated via improvement of histopathologic picture of hepatocytes and upregulation of total antioxidant capacity, reduced glutathione, catalase, glutathione peroxidase, superoxide dismutase, total protein, and albumin compared to TAA-treated rats. In conclusion, daily administration of sidr honey (5 g/kg BW) is a promising natural antioxidant and fibrosuppressive agent that could ameliorate liver fibrosis via downregulation of fibrosis genes including TGF-β1 and COL1a1 and HA and via enhancement of antioxidant system.

Abbreviated Magnetic Resonance Imaging Protocols in the Abdomen and Pelvis

In recent decades, the clinical applications for which magnetic resonance (MR) imaging is routinely used have expanded exponentially. MR imaging protocols have become increasingly complex, adversely affecting image acquisition and interpretation times. The MR imaging workflow has become a prime target for process improvement initiatives. There has been growing interest in the cultivation of abbreviated MR imaging protocols that evaluate specific clinical questions while reducing cost and increasing access. The overarching goal is to streamline the MR imaging workflow and reduce the time needed to obtain and report examinations by eliminating duplicative or unnecessary sequences without sacrificing diagnostic accuracy.

Simultaneous multislice rapid magnetic resonance elastography of the liver

To design and validate a rapid Simultaneous Multi-slice (SMS) Magnetic Resonance Elastography technique (MRE), which combines SMS acquisition, in-plane undersampling and an existing rapid Magnetic Resonance Elastography (MREr) scheme to allow accelerated data acquisition in healthy volunteers and comparison against MREr. SMS-MREr sequence was developed by incorporating SMS acquisition scheme into an existing MREr sequence that accelerates MRE acquisition by acquiring data during opposite phases of mechanical vibrations. The MREr sequence accelerated MRE acquisition by acquiring data during opposite phases of mechanical vibrations. Liver MRE was performed on 23 healthy subjects using MREr and SMS-MREr sequences, and mean stiffness values were obtained for manually drawn regions of interest. Linear correlation and agreement between MREr- and SMS-MREr-based stiffness values were investigated. SMS-MREr reduced the scan time by half relative to MREr, and allowed acquisition of four-slice MRE data in a single 17-second breath-hold. Visual comparison suggested agreement between MREr and SMS-MREr elastograms. A Pearson's correlation of 0.93 was observed between stiffness values derived from MREr and SMS-MREr. Bland-Altman analysis demonstrated good agreement, with -0.08 kPa mean bias and narrow limits of agreement (95% CI: 0.23 to -0.39 kPa) between stiffness values obtained using MREr and SMS-MREr. SMS can be combined with other fast MRE approaches to achieve further acceleration. This pushes the limit on the acceleration that can be achieved in MRE acquisition, and makes it possible to conduct liver MRE exams in a single breath-hold.

Nanofiber-expanded stem cells mitigate liver fibrosis: Experimental study

OBJECTIVES

This study examines a pretreatment strategy to strengthen the hepatic lineage divergence of mesenchymal stem cells (MSCs).

DESIGN AND METHODS

BMSCs were expanded in the presence or absence of nanofiber (NF) and treated with growth factors (GF) prior to transplantation. Thioacetamide (TA) was used for liver fibrosis induction and transplantation of NF-expanded BMSCs was compared biochemically and histologically to the cells expanded without NF scaffold.

RESULTS

The ultraweb NF caused better proliferation and characterization of MSCs. MSCs transplantation significantly improved liver functions, increased hepatic HGF and Bcl-2 levels, whereas decreased serum fibronectin, hepatic TNF-α and TGF-β1 levels. Hepatic HNF4α, FOXa2, CYP7a1 genes expression were enhanced while β-5-Tub and AFP genes expression were depressed. Histological study documented these results. Differentiated NF-MSCs showed pronounced enhancement of the aforementioned parameters as compared to differentiated MSCs in the absence of NF.

CONCLUSION

pretreatment with growth factors in the presence of NF augment homing, repopulation and hepatic differentiation abilities of MSCs and proves to be a promising approach for the treatment of liver fibrosis.

Cultured Mycelium Cordyceps sinensis allevi¬ates CCl4-induced liver inflammation and fibrosis in mice by activating hepatic natural killer cells

AIM

Recent evidence shows that cultured mycelium Cordyceps sinensis (CMCS) effectively protects against liver fibrosis in mice. Here, we investigated whether the anti-fibrotic action of CMCS was related to its regulation of the activity of hepatic natural killer (NK) cells in CCl4-treated mice.

METHODS

C57BL/6 mice were injected with 10% CCl4 (2 mL/kg, ip) 3 times per week for 4 weeks, and received CMCS (120 mg·kg(-1)·d(-1), ig) during this period. In another part of experiments, the mice were also injected with an NK cell-deleting antibody ASGM-1 (20 μg, ip) 5 times in the first 3 weeks. After the mice were sacrificed, serum liver function, and liver inflammation, hydroxyproline content and collagen deposition were assessed. The numbers of hepatic NK cells and expression of NKG2D (activation receptor of NK cells) on isolated liver lymphocytes were analyzed using flow cytometry. Desmin expression and cell apoptosis in liver tissues were studied using desmin staining and TUNEL assay, respectively. The levels of α-SMA, TGF-β, RAE-1δ and RAE-1ε in liver tissues were determined by RT-qPCR.

RESULTS

In CCl4-treated mice, CMCS administration significantly improved liver function, attenuated liver inflammation and fibrosis, and increased the numbers of hepatic NK cells and expression level of NKG2D on hepatic NK cells. Furthermore, CMCS administration significantly decreased desmin expression in liver tissues, and increased TUNEL staining adjacent to hepatic stellate cells. Injection with NK cell-deleting ASGM-1 not only diminished the numbers of hepatic NK cells, but also greatly accelerated liver inflammation and fibrosis in CCl4-treated mice. In CCl4-treated mice with NK cell depletion, CMCS administration decelerated the rate of liver fibrosis development, and mildly upregulated the numbers of hepatic NK cells but without changing NKG2D expression.

CONCLUSION

CMCS alleviates CCl4-induced liver inflammation and fibrosis via promoting activation of hepatic NK cells. CMCS partially reverses ASGM-1-induced depletion of hepatic NK cells.

K⁺-channel inhibition reduces portal perfusion pressure in fibrotic rats and fibrosis associated characteristics of hepatic stellate cells

BACKGROUND & AIMS

In liver fibrosis, activated hepatic stellate cells (HSC) secrete excess extracellular matrix, thus, represent key targets for antifibrotic treatment strategies. Intermediate-conductance Ca(2) (+) -activated K(+) -channels (KCa3.1) are expressed in non-excitable tissues affecting proliferation, migration and vascular resistance rendering KCa3.1 potential targets in liver fibrosis. So far, no information about KCa3.1 expression and their role in HSC exists. Aim was to quantify the KCa3.1 expression in HSC depending on HSC activation and investigation of antifibrotic properties of the specific KCa3.1 inhibitor TRAM-34 in vitro and in vivo.

METHODS

KCa3.1 expression and functionality were studied in TGF-β1-activated HSC by quantitative real time PCR, western-blot and patch-clamp analysis respectively. Effects of TRAM-34 on HSC proliferation, cell cycle and fibrosis-related gene expression were assessed by [(3) H]-thymidine incorporation, FACS-analysis and RT-PCR respectively. In vivo, vascular resistance and KCa3.1 gene and protein expression were determined in bile duct ligated rats by in situ liver perfusion, Taqman PCR and immunohistochemistry respectively.

RESULTS

Fibrotic tissues and TGF-β1-activated HSC exhibited higher KCa3.1-expressions than normal tissue and untreated cells. KCa3.1 inhibition with TRAM-34 reduced HSC proliferation by induction of cell cycle arrest and reduced TGF-β1-induced gene expression of collagen I, alpha-smooth muscle actin and TGF-β1 itself. Furthermore, TRAM-34 blocked TGF-β1-induced activation of TGF-β signalling in HSC. In vivo, TRAM-34 reduced the thromboxane agonist-induced portal perfusion pressure.

CONCLUSION

Inhibition of KCa3.1 with TRAM-34 downregulates fibrosis-associated gene expression in vitro, and reduces portal perfusion pressure in vivo. Thus, KCa3.1 may represent novel targets for the treatment of liver fibrosis.

Effect of Dahuang zhechong formula on liver fibrosis in patients with chronic hepatitis B: a meta-analysis

BACKGROUND

Dahuang zhechong formula has been used for the treatment of chronic hepatitis B, but its efficacy on the liver fibrosis is conflicting. We performed a meta-analysis to quantitatively investigate the efficacy of Dahuang zhechong formula as an adjunctive therapy treatment for liver fibrosis in patients with hepatitis B.

METHODS

We searched the PubMed, EMBASE, VIP database, China National Knowledge Infrastructure, and Wanfang database through January 2014. Only randomized controlled trials investigating Dahuang zhechong formula as an adjunctive therapy treatment for liver fibrosis in patients with chronic hepatitis B were selected.

RESULTS

Seventeen trials involving 1212 patients were included. Dahuang zhechong formula reduced serum hyaluronic acid level (standardized mean difference [SMD]=-1.27; 95% confidence interval [CI]: -1.72 to -0.83), type-III procollagen level (SMD=-1.71; 95%CI: -2.34 to -1.09), type-IV collagen level (SMD=-1.06; 95%CI: -1.41 to -0.70), and laminin level (SMD=-0.75; 95%CI: -0.89 to -0.62). In particular, subgroup analyses showed that patients who did not receive anti-viral agents have achieved a greater reduction in serum fibrosis markers.

CONCLUSIONS

Dahuang zhechong formula appears to reduce serum biomarkers of liver fibrosis in patients with chronic hepatitis B. However, robust conclusions cannot be reached due to the methodological flaws of the included trials.

Magnetic resonance elastography of liver

Magnetic resonance elastography (MRE) assesses tissue stiffness in vivo by imaging propagating shear waves through the tissues and processing the wave information. MRE is a robust technology with excellent technical success; is applicable in almost all patients and body habitus; and has excellent reproducibility, repeatability, and interobserver agreement for assessing liver stiffness. It is currently the most accurate noninvasive technique for detection and staging of liver fibrosis and has the potential to replace liver biopsy. This article describes the principles and technique of MRE, current clinical applications, and emerging clinical indications.

Determination of normal hepatic elasticity by using real-time shear-wave elastography

PURPOSE

To determine normal reference values of liver elasticity and measurement reliability by using real-time shear-wave elastography (SWE) in patients with a range of ages and body mass index (BMI) measurements, with presence or absence of hepatic steatosis.

MATERIALS AND METHODS

The institutional review board approved this study, and informed consent was waived because of the retrospective nature of the study. Two hundred thirty-eight patients who underwent SWE and ultrasonography-guided liver biopsies on the same day were identified retrospectively. The median kilopascal value of three consecutive measurements was used as a representative value for each subject. One hundred ninety-six patients who were potential donors for living-donor liver transplantation and had biopsy-proven normal (123 nonsteatotic and 73 steatotic) livers as the only histologic abnormality were included in the study. Reference ranges of normal hepatic elasticity were calculated by using lower and upper limits at the 2.5 and 97.5 percentiles. With the upper value of the reference range as a cutoff value, the sensitivity and specificity for the diagnosis of hepatic fibrosis were calculated. Measurement reliability was evaluated by using the intraclass correlation coefficient (ICC). To investigate the effects of potential confounding factors (age, hepatic steatosis, and BMI) on liver elasticity, the Pearson correlation test and the Student t test were performed.

RESULTS

The reference range of normal hepatic elasticity was 2.6-6.2 kPa. With 6.2 kPa as a cutoff value, the sensitivity and specificity for the diagnosis of hepatic fibrosis were 91% (20 of 22 subjects) and 95.9% (188 of 196 subjects), respectively. The overall ICC for the elasticity measurements was 0.924. The potential confounding factors that we considered had negligible effects on the elasticity values.

CONCLUSION

Hepatic elasticity values measured with SWE in histologically proven normal livers ranged from 2.6 to 6.2 kPa, with high measurement reliability. The effect of the potential confounding factors on liver elasticity was negligible.

Rapid acquisition technique for MR elastography of the liver

Magnetic resonance elastography (MRE) of the liver is a novel noninvasive clinical diagnostic tool to stage fibrosis based on measured stiffness. The purpose of this study is to design, evaluate and validate a rapid MRE acquisition technique for noninvasively quantitating liver stiffness which reduces by half the scan time, thereby decreasing image registration errors between four MRE phase offsets. In vivo liver MRE was performed on 16 healthy volunteers and 14 patients with biopsy-proven liver fibrosis using the standard clinical gradient recalled echo (GRE) MRE sequence (MREs) and a developed rapid GRE MRE sequence (MREr) to obtain the mean stiffness in an axial slice. The mean stiffness values obtained from the entire group using MREs and MREr were 2.72±0.85 kPa and 2.7±0.85 kPa, respectively, representing an insignificant difference. A linear correlation of R(2)=0.99 was determined between stiffness values obtained using MREs and MREr. Therefore, we can conclude that MREr can replace MREs, which reduces the scan time to half of that of the current standard acquisition (MREs), which will facilitate MRE imaging in patients with inability to hold their breath for long periods.

Indirect prediction of liver fibrosis by quantitative measurement of spleen stiffness using the FibroScan system

OBJECTIVES

To evaluate quantitative measurement of spleen stiffness for indirect assessment of liver fibrosis in patients with chronic hepatitis B and to correlate spleen stiffness with liver stiffness using pathologic examination as a reference standard.

METHODS

Sixty patients with clinically confirmed chronic hepatitis B (n = 54) and liver cirrhosis (n = 6) were enrolled. Quantitative stiffness measurements (kilopascals) were obtained from spleen and liver parenchyma with the FibroScan system (Echosens, Paris, France). Correlation analyses were performed between spleen and liver stiffness and between spleen stiffness and liver fibrosis stages. The diagnostic performance of spleen stiffness for indirect prediction of liver fibrosis was estimated by receiver operating characteristic curves.

RESULTS

Both spleen and liver stiffness increased as liver fibrosis progressed. Spleen stiffness values had a positive correlation with liver stiffness values in all patients (Pearson r = 0.810; P < .001). The correlation between spleen stiffness and fibrosis stages was statistically significant (Spearman r = 0.833; P < .001). The areas under the receiver operating characteristic curves for spleen stiffness were 0.902 (95% confidence interval [CI], 0.825-0.978) for stage S1 (fibrous portal expansion and limited perisinusoidal or lobular fibrosis) or higher, 0.927 (95% CI, 0.852-1.0) for S2 (periportal fibrosis and few fibrous septa but intact architecture) or higher, 0.962 (95% CI, 0.918-1.0) for S3 (numerous fibrous septa with architectural distortion but no obvious cirrhosis) or higher, and 0.983 (95% CI, 0.957-1.0) for S4 (cirrhosis) (all P < .001). The differences between the areas under the curves for spleen and liver stiffness in liver fibrosis staging were not statistically significant (P = .115-.756).

CONCLUSIONS

Quantitative measurement of spleen stiffness is a feasible and promising technique for estimating liver fibrosis. The overall diagnostic performance of spleen stiffness for liver fibrosis staging is comparable with that of liver stiffness.

Protective effect of the herbal medicine Gan‑fu‑kang against carbon tetrachloride‑induced liver fibrosis in rats

The aim of the present study was to investigate the effect of a herbal medicine formula, Gan-fu-kang (GFK), on the treatment of liver fibrosis in rats and the mechanisms via which it exerts its effect. Liver fibrosis was induced in rats by subcutaneous injection of carbon tetrachloride (CCl4) at 0.5 mg/kg body weight, twice a week for 8 weeks. The rats were randomly selected to receive saline or GFK at 31.25, 312.5 or 3,125 mg/kg body weight/day between weeks 9 and 20. An additional group of rats without CCl4 injection was used as the baseline. In the liver fibrosis model rats, an increase in plasma liver enzymes, fibrotic markers in serum and liver fibrosis, production of α-smooth muscle actin, matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1, synthesis of collagen and activation of the Wnt/β-catenin signaling pathway were observed. GFK administration was found to significantly reduce these changes. Results of this study demonstrate that GFK has a protective and therapeutic effect on liver fibrosis induced by CCl4, which may be associated with its inhibitory activity on HSC proliferation and collagen synthesis, effectively downregulating Wnt/β-catenin signaling.

Magnetic resonance elastography of liver: technique, analysis, and clinical applications

Many pathological processes cause marked changes in the mechanical properties of tissue. MR elastography (MRE) is a noninvasive MRI based technique for quantitatively assessing the mechanical properties of tissues in vivo. MRE is performed by using a vibration source to generate low frequency mechanical waves in tissue, imaging the propagating waves using a phase contrast MRI technique, and then processing the wave information to generate quantitative images showing mechanical properties such as tissue stiffness. Since its first description in 1995, published studies have explored many potential clinical applications including brain, thyroid, lung, heart, breast, and skeletal muscle imaging. However, the best-documented application to emerge has been the use of MRE to assess liver disease. Multiple studies have demonstrated that there is a strong correlation between MRE-measured hepatic stiffness and the stage of fibrosis at histology. The emerging literature indicates that MRE can serve as a safer, less expensive, and potentially more accurate alternative to invasive liver biopsy which is currently the gold standard for diagnosis and staging of liver fibrosis. This review describes the basic principles, technique of performing a liver MRE, analysis and calculation of stiffness, clinical applications, limitations, and potential future applications.

Fuzheng Huayu inhibits carbon tetrachloride-induced liver fibrosis in mice through activating hepatic NK cells

AIM OF THE STUDY

Fuzheng Huayu (FZHY) is a Chinese compound herbal preparation which consists of six Chinese herbs. This study examines the preventative effects of FZHY on liver fibrosis induced by carbon tetrachloride (CCl(4)) and explores its possible mechanisms of action.

MATERIALS AND METHODS

Liver fibrosis was induced in male C57BL/6N mice by injecting a 10% CCl(4) solution intraperitoneal twice a week for six weeks. After 6 weeks of treatment, serum ALT and AST assay, liver tissue histological examination and immunostaining were carried out to examine the liver function and fibrosis degree. The expression levels of alpha-smooth muscle actin (SMA) were measured by quantitative real-time PCR and western blot. Hepatic natural killer (NK) cells were isolated from liver and evaluated by FACS.

RESULTS

Upon pathological examination, the FZHY-treated mice showed significantly reduced liver damage. The expression of α-SMA increased markedly upon treatment with CCl(4) and the increase was reversed by FZHY treatment. FZHY treatment also enhanced the activation of hepatic NK cells and the production of interferon-gamma (IFN-γ). The protective effects of FZHY were reversed in the mice that were depleted of NK cells by anti-ASGM-1 Ab treatment.

CONCLUSIONS

FZHY can efficiently inhibit CCl(4)-induced liver fibrosis. Furthermore, the depletion of NK cells attenuates the protective effects of FZHY. We conclude that FZHY could be an effective drug for liver fibrosis, and its mechanism of action involves the activation of hepatic NK cells.

Hepatic fibrosis: evaluation with semiquantitative contrast-enhanced CT

PURPOSE

To evaluate the feasibility of using contrast material-enhanced computed tomographic (CT) measurements of hepatic fractional extracellular space (fECS) and macromolecular contrast material (MMCM) uptake to measure severity of liver fibrosis.

MATERIALS AND METHODS

All procedures were approved by and executed in accordance with University of California, San Francisco, institutional animal care and use committee regulations. Twenty-one rats that received intragastric CCl(4) for 0-12 weeks were imaged with respiratory-gated micro-CT by using both a conventional contrast material and a novel iodinated MMCM. Histopathologic hepatic fibrosis was graded qualitatively by using the Ishak fibrosis score and quantitatively by using morphometry of the fibrosis area. Hepatic fECS and MMCM uptake were calculated for each examination and correlated with histopathologic findings by using uni- and multivariate linear regressions.

RESULTS

Ishak fibrosis scores ranged from a baseline of 0 in untreated animals to a maximum of 5. Histopathologic liver fibrosis area increased from 0.46% to 3.5% over the same interval. Strong correlations were seen between conventional contrast-enhanced CT measurements of fECS and both the Ishak fibrosis scores (R(2) = 0.751, P < .001) and the fibrosis area (R(2) = 0.801, P < .001). Strong negative correlations were observed between uptake of MMCM in the liver and Ishak fibrosis scores (R(2) = 0.827, P < .001), as well as between uptake of MMCM in the liver and fibrosis area (R(2) = 0.643, P = .001). Multivariate linear regression analysis showed a trend toward independence for fECS and MMCM uptake in the prediction of Ishak fibrosis scores, with an R(2) value of 0.86 (P = .081 and P = .033, respectively).

CONCLUSION

Contrast-enhanced CT measurements of fECS and MMCM uptake are individually capable of being used to estimate the degree of early hepatic fibrosis in a rat model.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12112452/-/DC1.

Renal protective effect of xiao-chai-hu-tang on diabetic nephropathy of type 1-diabetic mice

Xiao-Chai-Hu-Tang (XCHT), a traditional Chinese medicine formula consisting of seven medicinal plants, is used in the treatment of various diseases. We show here that XCHT could protect type-1 diabetic mice against diabetic nephropathy, using streptozotocin (STZ)-induced diabetic mice and high-glucose (HG)-exposed rat mesangial cell (RMC) as models. Following 4 weeks of oral administration with XCHT, renal functions and renal hypertrophy significantly improved in the STZ-diabetic mice, while serum glucose was only moderately reduced compared to vehicle treatment. Treatment with XCHT in the STZ-diabetic mice and HG-exposed RMC resulted in a decrease in expression levels of TGF-β1, fibronectin, and collagen IV, with concomitant increase in BMP-7 expression. Data from DPPH assay, DHE stain, and CM-H₂DCFDA analysis indicated that XCHT could scavenge free radicals and inhibit high-glucose-induced ROS in RMCs. Taken together, these results suggest that treatment with XCHT can improve renal functions in STZ-diabetic mice, an effect that is potentially mediated through decreasing oxidative stress and production of TGF-β1, fibronectin, and collagen IV in the kidney during development of diabetic nephropathy. XCHT, therefore merits further investigation for application to improve renal functions in diabetic disorders.

Antifibrotic effects of Artemisia capillaris and Artemisia iwayomogi in a carbon tetrachloride-induced chronic hepatic fibrosis animal model

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia capillaris and Artemisia iwayomogi, both members of the Compositae family, have been indiscriminately used for various liver disorders as traditional hepatotherapeutic medicines in Korea for many years.

AIM OF THE STUDY

In this study, the anti-hepatofibrotic effects of Artemisia capillaris and Artemisia iwayomogi were comparatively analyzed using a carbon tetrachloride (CCl(4))-induced liver fibrosis rat model.

MATERIALS AND METHODS

Hepatic fibrosis was induced via a 10-week course of intraperitoneal CCl(4) injections (50% dissolved in olive oil, 2mL/kg, twice per week). Water extract of Artemisia capillaris (AC) or Artemisia iwayomogi (AI) was orally administered six times per week from the 5th to the 10th week.

RESULTS

AI (50mg/kg) significantly attenuated the CCl(4)-induced excessive release of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in serum (p<0.05), and hydroxyproline and malondialdehyde (MDA) contents in liver tissue (p<0.05). Further, AI markedly ameliorated the depletion of total antioxidant capacity (TAC), glutathione (GSH), and superoxide dismutase (SOD) in liver tissue (p<0.01). Unexpectedly, AC did not exert any effects on the above parameters. Histopathological and immunohistochemical analyses revealed that AI drastically reduced inflammation, necrosis, fatty infiltration, collagen accumulation, and activation of hepatic satellite cells in liver tissue. These changes were not observed with AC treatment. Several critical genes of fibrosis-related cytokines including transforming growth factor beta (TGF-β), platelet-derived growth factor beta (PDGF-β), and alpha smooth muscle actin (α-SMA) were more prominently downregulated by AI compared to AC treatment.

CONCLUSION

Our results show that AI exerts greater hepatoprotective and anti-fibrotic effects as compared with AC via enhancing antioxidant capacity and downregulating fibrogentic cytokines.

Effects and mechanisms of Acremoniumterricola milleretal mycelium on liver fibrosis induced by carbon tetrachloride in rats

Acremoniumterricola milleretal mycelium (AMM) is one of the most precious traditional Chinese medicines. It has numerous protective effects on organs, and has been used in Chinese herb prescription to treat refractory diseases. Our preliminary studies demonstrated that AMM had hepatoprotective activity in acute liver injury. We further investigated the effects of AMM on liver fibrosis in rats induced by carbon tetrachloride (CCl(4)) and explore its possible mechanisms. The animal model was established by injection with 50% CCl(4) subcutaneously in male Sprague-Dawley rats twice a week for eight weeks. Meanwhile, AMM (175, 350 and 700 mg/kg) was administered intragastrically per day until sacrifice. We found that treatment with AMM (175, 350 and 700 mg/kg) decreased CCl(4)-induced elevation of serum transaminase activities, hyaluronic acid, laminin and procollagen type III levels, and contents of hydroxyproline in liver tissues. It also restored the decreased SOD and GSH-Px activities and inhibited the formation of lipid peroxidative products during CCl(4) treatment. Moreover, AMM (350 and 700 mg/kg) decreased the elevation of TGF-β1 by 19.6% and 34.3%, respectively. In the pathological study, liver injury and the formation of liver fibrosis in rates treated by AMM were improved significantly. Immunoblot analysis showed that AMM (175, 350 and 700 mg/kg) inhibited Smad 2/3 phosphorylation, and elevated inhibitor Smad 7 expression. These results suggested that AMM could protect liver damage and inhibit the progression of hepatic fibrosis induced by CCl(4), and its mechanisms might be associated with its ability to scavenge free radicals, decrease the level of TGF-β1 and block TGF-β/Smad signaling pathway.

Indole-3-carbinol enhances the resolution of rat liver fibrosis and stimulates hepatic stellate cell apoptosis by blocking the inhibitor of κB kinase α/inhibitor of κB-α/nuclear factor-κB pathway

Hepatic stellate cells (HSC) play a pivotal role in liver fibrosis, and the clearance of activated HSC by apoptosis is associated with the resolution of liver fibrosis. The development of strategies that promote this process in a selective way is therefore important. We evaluated the effects of indole-3-carbinol (I3C), a nutritional component derived from vegetables from the Brassica family, on liver fibrosis and HSC apoptosis. The in vivo therapeutic effects of I3C were monitored in three rat models of liver fibrosis induced by porcine serum, bile duct ligation, or multiple hepatotoxic factors, and its proapoptotic effect and molecular mechanism were studied in vitro in HSC-T6, a rat HSC line. The results showed that I3C treatment significantly reduced the number of activated HSC in the livers of rats with liver fibrosis. In histopathology, I3C reduced hepatocyte degeneration and necrosis, accelerated collagen degradation, and promoted the reversal of liver fibrosis. I3C prescribed to HSC-T6 resulted in morphologic alterations typical of apoptosis and DNA cleavage to a nucleosomal ladder. Moreover, I3C significantly increased the HSC-T6 apoptosis rate and the expression ratio of Bax to Bcl-2. High-throughput protein array analysis indicated that the tumor necrosis factor-α/nuclear factor-κB (NF-κB) signal pathway participated in I3C-induced HSC-T6 apoptosis. Western blot and electrophoretic mobility-shift assay confirmed that I3C inhibited the phosphorylation of inhibitor of κB kinase α and inhibitor of κB-α and NF-κB DNA binding activity. In conclusion, I3C could promote the reverse process of liver fibrosis in vivo and induce apoptosis of activated HSC in vitro, which indicates the use of I3C as a potential therapeutic agent in liver fibrosis treatment.

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.

Preventive effects of a fractioned polysaccharide from a traditional Chinese herbal medical formula (Yu Ping Feng San) on carbon tetrachloride-induced hepatic fibrosis

OBJECTIVES

The study was to investigate the prevention effects and possible mechanism of Yu Ping Feng San fractioned polysaccharide (YPF-P) on CCl(4)-induced liver fibrosis in rats.

METHODS

YPF-P was prepared from root of Astragalus membranaceus, rhizome of Atractylodes macrocephaia and root of Raidix saposhnikoviae, and compared with polysaccharide from root of Astragalus membranaceus (AP). Hepatic fibrosis was induced by subcutaneous injection with carbon tetrachloride twice weekly for 12 weeks in Sprague-Dawley rats. YPF-P, AP and colchicine were administered intragastrically daily to carbon tetrachloride-treated rats. Histopathological changes of the liver and hepatic stellate cells were evaluated by Masson staining and transmission electron microscopy, respectively. Markers of fibrosis were determined by radioimmunoassay, biochemistry assay and ELISA. The mRNA expressions of tissue inhibitor of metalloproteinase-1 (TIMP-1), matrix metalloproteinase-13 (MMP-13), procollagen I and collagen III were detected by RT-PCR.

KEY FINDINGS

YPF-P dose-dependently alleviated the degree of liver fibrosis and inhibited hepatic stellate cell transformation into myofibroblast-like cells, markedly reduced the elevated levels of hyaluronic acid, laminin, type IV collagen, type III procollagen, hydroxyproline and transforming growth factor beta-1, suppressed procollagen I, collagen III and TIMP-1 expression, and improved the TIMP-1/MMP-13 ratio. MMP-13 expression was only promoted moderately by YPF-P. Compared with AP, YPF-P showed more potency on most markers except laminin, type IV collagen and MMP-13 mRNA.

CONCLUSIONS

YPF-P prevented the progress of rat liver fibrosis induced by carbon tetrachloride and had a more potent preventative effect. The preventative effect may be associated with the ability of YPF-P to inhibit the synthesis of matrix collagen and balance the TIMP/MMP system.

Liver contrast enhanced ultrasound perfusion imaging in the evaluation of chronic hepatitis C fibrosis: preliminary results

We wanted to determine whether liver contrast-enhanced ultrasound (CEUS)-derived peak signal intensity (PSI) and peak signal intensity/time (PIT) predict liver fibrosis in chronic hepatitis C (CHC). Forty-nine patients with CHC (METAVIR classification) and 10 control subjects were included in the study. After a bolus of 2.4 mL SonoVue (Bracco Imaging, Milan, Italy) solution was injected into a peripheral vein, the right lobe of the liver containing the right portal vein was scanned in a transverse section. Two-dimensional sonography was performed using the Philips iU22 ultrasound system (Philips Healthcare, Best, the Netherlands). A 1.0-5.0-MHz (C5-1) wideband convex transducer was used, applying the following settings in all cases. Regions of interest were manually drawn over the right liver lobe and over the portal vein (PV). Liver parenchyma PSI (LPpsi) and PIT (LPpit), portal vein PSI (PVpsi) and PIT (PVpit) were automatically calculated. δPSI was defined as the difference between PVpsi and LPpsi. A significant correlation was observed between PA(PSI) and fibrosis scores. When patients were stratified according to their LPpsi, a significant difference was achieved only between patients with fibrosis score 0-1 vs. 2-3 and 2 vs. 4. Statistically significant differences between all fibrosis scores, except 0 vs. 1 and 3 vs. 4 were observed when δPSI was used to stratify patients. Overall diagnostic accuracy of LPpsi and δPSI measurement for severe fibrosis by area under the receiving operator characteristic curve analysis was, respectively, 0.87 and 0.88. We suggest that liver CEUS perfusion could have the potential to be used as a complementary tool for the evaluation of liver fibrosis. However, further large-scale studies are required to accurately assess its accuracy in the evaluation of liver fibrosis.

Expression of survivin in activated hepatic stellate cells and effect of transfection of antisense oligonucleotide targeting the survivin gene on apoptosis of HSC-T6 cells

AIM: To investigate the expression of survivin in activated hepatic stellate cell (HSC) and the effect of transfection of antisense oligonucleotide (ASODN) targeting the survivin gene on apoptosis of HSC-T6 cells.

METHODS: The experiment set the control group which not added liposome and oligonucleotide (ODN), liposome group which only added liposome, sense oligonucleotide (SODN) group (1 000 nmol/L) and 400, 800, 1 000 nmol/L ASODN group. The expression of survivin protein in activated HSC, hepatic carcinoma cells, and normal liver cells was detected by immunofluorescence. ASODN targeting the survivin gene was transfected into HSC-T6 cells with LipofectamineTM 2000, and transfection efficiency was detected by fluorescence microscopy. Forty-eight hours after transfection, the changes in survivin mRNA and protein expression were assessed by RT-PCR and Western blot, respectively, and cell apoptosis was measured by PI staining and flow cytometry.

RESULTS: The positive rate of survivin expression in activated HSC was significantly higher than that in normal liver cells (66.07% ± 8.55% vs 9.74% ± 2.68%, P < 0.05). The positive rate of survivin expression was highest in hepatic carcinoma cells among the three groups of cells (69.41% ± 9.10%). Strong green fluorescence was observed by fluorescence microscopy in cells transfected with different concentrations of ASODN, and the transfection efficiency reached 80%. Compared with blank control cells and cells transfected with empty lipofectamineTM 2000 or control oligonucleotide, the expression levels of survivin mRNA (0.94 ± 0.03, 0.95 ± 0.04 and 0.92 ± 0.04 vs 0.64 ± 0.02, 0.54 ± 0.02 and 0.26 ± 0.01) and protein (0.84 ± 0.02, 0.82 ± 0.03 and 0.81 ± 0.02 vs 0.53 ± 0.02, 0.38 ± 0.01 and 0.20 ± 0.01) were significantly decreased (all P < 0.01), and the apoptosis rate (19.00% ± 0.53%, 29.80% ± 1.54% and 48.70% ± 2.00%, respectively) significantly increased (all P < 0.01) in cells transfected with different concentrations of ASODN.

CONCLUSION: Survivin is highly expressed in activated HSC-T6 cells. Down-regulation of survivin expression by transfection of ASODN targeting the survivin gene can induce apoptosis of HSC-T6 cells.

Toward surface quantification of liver fibrosis progression

Monitoring liver fibrosis progression by liver biopsy is important for certain treatment decisions, but repeated biopsy is invasive. We envision redefinition or elimination of liver biopsy with surface scanning of the liver with minimally invasive optical methods. This would be possible only if the information contained on or near liver surfaces accurately reflects the liver fibrosis progression in the liver interior. In our study, we acquired the second-harmonic generation and two-photon excitation fluorescence microscopy images of liver tissues from bile duct-ligated rat model of liver fibrosis. We extracted morphology-based features, such as total collagen, collagen in bile duct areas, bile duct proliferation, and areas occupied by remnant hepatocytes, and defined the capsule and subcapsular regions on the liver surface based on image analysis of features. We discovered a strong correlation between the liver fibrosis progression on the anterior surface and interior in both liver lobes, where biopsy is typically obtained. The posterior surface exhibits less correlation with the rest of the liver. Therefore, scanning the anterior liver surface would obtain similar information to that obtained from biopsy for monitoring liver fibrosis progression.

Hepatic fibrosis is enhanced and accompanied by robust oval cell activation after chronic carbon tetrachloride administration to Egr-1-deficient mice

The transcription factor early growth response (Egr)-1 regulates the expression of genes required for execution of the wound healing response. Multiple cycles of injury, coupled to incomplete wound healing, lead to fibrosis. Therefore, we hypothesized that Egr-1 is required for the development of hepatic fibrosis. To test this hypothesis, we exposed wild-type and egr-1(-/-) mice to acute or chronic carbon tetrachloride (CCl(4)). Acute CCl(4) exposure established a profibrotic milieu in the liver, including activation of hepatic stellate cells as well as expression of type 1 collagen genes and tissue inhibitor of matrix metalloproteinase 1 in both wild-type and egr-1(-/-) mice. This response was exacerbated in egr-1(-/-) mice. After chronic CCl(4) exposure, hepatic fibrosis was established in both genotypes; however, the fibrotic response was profoundly worsened in Egr-1-deficient mice. Importantly, enhanced fibrosis in egr-1(-/-) mice was accompanied by a robust activation of the oval cell response, suggesting more severe liver injury and/or reduced hepatocyte proliferation when compared with wild-type mice. Hepatic expression of genes indicative of oval cell activation, as well as the number of cells expressing A6, a mouse oval cell marker, was greater in egr-1(-/-) mice. Taken together, these data reveal novel roles for Egr-1 as a negative regulator of both CCl(4)-induced hepatic fibrosis and the oval cell response.

Abdominal magnetic resonance elastography

Magnetic resonance elastography (MRE) is a magnetic resonance imaging-based technique for quantitatively assessing the mechanical properties of tissues based on the propagation of shear waves. Multiple studies have described many potential applications of MRE, from characterizing tumors to detecting diffuse disease processes. Studies have shown that MRE can be successfully implemented to assess abdominal organs. The first clinical application of MRE to be well documented is the detection and characterization of hepatic fibrosis, which systematically increases the stiffness of liver tissue. In this diagnostic role, it offers a safer, less expensive, and potentially more accurate alternative to invasive liver biopsy. Emerging results suggest that measurements of liver and spleen stiffness may provide an indirect way to assess portal hypertension. Preliminary studies have demonstrated that it is possible to use MRE to evaluate the mechanical properties of other abdominal structures, such as the pancreas and kidneys. Steady technical progress in developing practical protocols for applying MRE in the abdomen and the pelvis provides opportunities to explore many other potential applications of this emerging technology.

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

AIM

CGX is a modification of a traditional herbal medicine for "liver cleaning," which is used to treat various chronic liver disorders in oriental clinics. This study investigated the antifibrotic effects and associated mechanisms of CGX.

MATERIALS AND METHODS

Liver fibrosis was induced in rats by dimethylnitrosamine (DMN; 10 mg kg(-1), ip) injection on 3 consecutive days per week for 4 weeks. CGX (100 or 200 mg kg(-1), po) was administrated once a day for 4 weeks. Three cell lines (HepG2, RAW 264.7, and HSC-T6) were used to examine its mechanisms.

RESULTS

CGX treatment dramatically ameliorated the change in liver and spleen weight and serum albumin (p<0.01), aspartate transaminase (p<0.01), alanine transaminase (p<0.01), alkaline phosphatase (p<0.01), and total bilirubin (p<0.01) levels. Histopathologically, CGX administration decreased necrosis, inflammatory cell infiltration, and collagen accumulation. The antifibrotic effects of CGX were confirmed from hydroxyproline determination and the reduction in the numbers of activated hepatic stellate cells. In addition, antioxidant proteins, glutathione content, and glutathione peroxidase, catalase, and superoxide dismutase activities were maintained in the CGX-treated groups compared with the DMN group. CGX downregulated fibrosis-related genes (inducible nitric oxide synthase, tumor necrosis factor-alpha, transforming growth factor-beta, connective tissue growth factor, and platelet-derived growth factor-beta) and decreased the protein levels of profibrotic cytokines (transforming growth factor-beta and platelet-derived growth factor-beta) in liver tissues. In the cell line-based studies, CGX showed supportive effects, such as the protection of hepatocytes from CCl(4)-toxicity, inhibition of NO production in RAW 264.7 cells, and inactivation of hepatic stellate cells.

CONCLUSION

These results demonstrated the antifibrotic effects of CGX and the corresponding mechanisms associated with sustaining the antioxidative system and inhibiting hepatic stellate cell activation via the downregulation of fibrogenic cytokines.

Experimental evidence for the protective effects of coffee against liver fibrosis in SD rats

BACKGROUND

Coffee is one of the most commonly consumed beverages worldwide. Accumulating clinical evidence has shown an inverse relationship between coffee and liver cirrhosis. We investigated the protective effect of coffee against liver fibrosis and underlying molecular mechanisms using a dimethylnitrosamine (DMN)-induced liver fibrosis model.

RESULTS

Coffee administration significantly prevented the deterioration of body weight, organ weight, and serum biochemistry by DMN treatment. Histopathological examination revealed that necrosis/inflammation and fibrotic septa decreased significantly in coffee-treated rats compared to those treated with DMN and water. Coffee administration also significantly inhibited the accumulation of hydroxyproline (P < 0.001) and the production of malondialdehyde (P < 0.05), as well as stellate cell activation caused by DMN injection. Coffee protected the depletion of glutathione, superoxide dismutase, and catalase in liver tissue. In addition, coffee treatment inhibited the gene expression of inducible nitric oxide synthase, transforming growth factor (TGF)-beta, tumor necrosis factor-alpha, interleukin-1, and platelet-derived growth factor (PDGF)-beta in liver tissues, and lowered the concentration of TGF-beta and PDGF-beta in liver. Coffee inhibited NO production by macrophages.

CONCLUSION

Coffee exerts protective effects against liver fibrosis via antioxidant action and the suppression of fibrogenic cytokines, TGF-beta and PDGF-beta.

Antifibrotic effects of chronic baicalein administration in a CCl4 liver fibrosis model in rats

Baicalein was a major bioactive flavonoid derived from Radix Scutellariae in Xiao-Chai-Hu-Tang which was commonly used to treat chronic hepatitis and liver fibrosis in China. The aim of this study was to assess whether chronic baicalein administration could prevent liver fibrosis induced by carbon tetrachloride (CCl(4)) in rats and investigate its possible protective mechanism. The antifibrotic effects of baicalein were assessed directly by hepatic histology and indirectly by measuring levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatic hyaluronic acid, laminin and procollagen type III (PCIII) in serum, as well as hydroxyproline and matrix metalloproteinases (MMPs) in liver. In addition, we further investigated protein synthesis of platelet derived growth factor (PDGF) beta receptor which has been identified as attractive target for therapeutic intervention. CCl(4) treatment increased levels of AST, ALT, hyaluronic acid, laminin, and PCIII in serum, as well as hydroxyproline and MMPs in liver. Baicalein treatment (20, 40, or 80 mg/kg for 10 weeks) dose-dependently decreased levels of these markers. Baicalein also reduced inflammation, destruction of liver architecture, and collagen accumulation and significantly inhibited protein synthesis of PDGF-beta receptor. Together, our results suggest that chronic baicalein administration inhibits stellate cell activation and proliferation by the down-regulation of PDGF-beta receptor and prevents the development of CCl(4) induced liver fibrosis in rats.

Effect of Fuzheng Huayu formula and its actions against liver fibrosis

Liver fibrosis is a common histological process to develop into cirrhosis in various chronic liver diseases including chronic hepatitis and fatty liver. Therefore anti-liver fibrosis is very important strategy to treat chronic liver diseases. Fuzheng Huayu (FZHY), a preparation containing herbs such as Radix Salvia Miltiorrhizae, Cordyceps, Semen Persicae, was formulated on the basis of Chinese medicine theory in treating liver fibrosis and was approved. Pharmacological studies and clinical trials demonstrate that FZHY has a significant effect against liver fibrosis and that many of the pharmacological actions are attributable to the effect. This article reviews the effects and actions of FZHY, in particular the effects observed from clinical trials in treating liver fibrosis caused by chronic hepatitis B and the actions on inhibition of hepatic stellate cell activation, protection of hepatocytes and inhibition of hepatic sinusoidal capillarization. This article also reviews the coordinated effects of the constituent herbs of FZHY and the actions of their active compounds such as salvianonic acid B (SA-B) on liver fibrosis.

Can imaging modalities diagnose and stage hepatic fibrosis and cirrhosis accurately?

The accurate diagnosis and staging of hepatic fibrosis is crucial for prognosis and treatment of liver disease. The current gold standard, liver biopsy, cannot be used for population-based screening, and has well known drawbacks if used for monitoring of disease progression or treatment success. Our objective was to assess performance and promise of radiologic modalities and techniques as alternative, noninvasive assessment of hepatic fibrosis. A systematic review was conducted. Six hundred twenty-eight studies were identified via electronic search. One hundred fifty-three papers were reviewed. Most described techniques that could differentiate between cirrhosis or severe fibrosis and normal liver. Accurate staging of fibrosis or diagnosis of mild fibrosis was often not achievable. Ultrasonography is the most common modality used in the diagnosis and staging of hepatic fibrosis. Elastographic measurements, either ultrasonography-based or magnetic resonance-based, and magnetic resonance diffusion weighted imaging, show the most promise for accurate staging of hepatic fibrosis. Most currently available imaging techniques can detect cirrhosis or significant fibrosis reasonably accurately. However, to date only magnetic resonance elastography has been able to stage fibrosis or diagnose mild disease. Utrasonographic elastography and magnetic resonance diffusion weighted appear next most promising.

Protective effect of extract from Paeonia lactiflora and Astragalus membranaceus against liver injury induced by bacillus Calmette-Guérin and lipopolysaccharide in mice

Paeonia lactiflora and Astragalus membranaceus are two popular traditional Chinese medicines, commonly used in Chinese herb prescription to treat liver disease. The extract from the roots of P. lactiflora and A. membranaceus demonstrated better hepatoprotective activity than the herbs used individually as shown in our previous studies. The present study was carried out to investigate the effects of P. lactiflora and A. membranaceus extract on immunological liver injury in mice induced by Bacillus Calmette-Guérin and lipopolysaccharide (BCG/LPS) and to explore a possible mechanism. After administration of P. lactiflora and A. membranaceus (60, 120 and 240 mg/kg, intragastrically) daily for 10 days, the extract significantly reduced the degree of liver damage in BCG/LPS-induced liver injury, as well as the elevation of serum transaminase activities and level of nitric oxide in live injury mice. The extract also restored the decrease in superoxide dismutase and glutathione peroxidase activities and inhibited the formation of lipid peroxidative products. Moreover, P. lactiflora and A. membranaceus (60, 120 and 240 mg/kg, intragastrically) repressed high levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) from peritoneal macrophages. In the primary cultured Kupffer cells, P. lactiflora and A. membranaceus also significantly decreased the production of TNF-alpha and IL-1 in cells stimulated with LPS (5 microg/ml). These results suggest that P. lactiflora and A. membranaceus have a protective effect on BCG/LPS-induced liver injury mice, which might be associated with the antioxidant properties, ability to reduce nitric oxide production and suppression of Kupffer cell activity and pro-inflammatory mediator and cytokines production.

Targeting liver myofibroblasts: a novel approach in anti-fibrogenic therapy

Chronic liver disease results in a liver-scarring response termed fibrosis. Excessive scarring leads to cirrhosis, which is associated with high morbidity and mortality. The only treatment for liver cirrhosis is liver transplantation; therefore, much attention has been directed toward therapies that will slow or reverse fibrosis. Although anti-fibrogenic therapies have been shown to be effective in experimental animal models, licensed therapies have yet to emerge. A potential problem for any anti-fibrogenic therapy in the liver is the existence of the body’s major drug metabolising cell (the hepatocyte) adjacent to the primary fibrosis-causing cell, the myofibroblast. This article reviews the development of a human recombinant single-chain antibody (scAb) that binds to the surface of myofibroblasts. This antibody binds specifically to myofibroblasts in fibrotic mouse livers. When conjugated with a compound that stimulates myofibroblast apoptosis, the antibody directs the specific apoptosis of myofibroblasts with greater specificity and efficacy than the free compound. The antibody also reduces the adverse effect of liver macrophage apoptosis and—in contrast to the free compound—reversed fibrosis in the sustained injury model used. These data suggest that specifically stimulating the apoptosis of liver myofibroblasts using a targeting antibody has potential in the treatment of liver fibrosis.

Quantitative assessment of hepatic fibrosis in an animal model with magnetic resonance elastography

Chronic liver disease is a world-wide problem that causes progressive hepatic fibrosis as a hallmark of progressive injury. At present, the gold standard for diagnosing hepatic fibrosis is liver biopsy, which is an invasive method with many limitations, including questionable accuracy and risks of complications. MR elastography (MRE), a phase-contrast MRI technique for quantitatively assessing the mechanical properties of soft tissues, is a potential noninvasive diagnostic method to assess hepatic fibrosis. In this work, MRE was evaluated as a quantitative method to assess the in vivo mechanical properties of the liver tissues in a knockout animal model of liver fibrosis. This work demonstrates that the shear stiffness of liver tissue increases systematically with the extent of hepatic fibrosis, as measured by histology. A linear correlation between liver stiffness and fibrosis extent was well-defined in this animal model. An additional finding of the study was that fat infiltration, commonly present in chronic liver disease, does not significantly correlate with liver stiffness at each fibrosis stage and thus does not appear to interfere with the ability of MRE to assess fibrosis extent. In conclusion, MRE has the potential not only for assessing liver stiffness, but also for monitoring potential therapies for hepatic fibrosis.

Retinoic acid signaling sensitizes hepatic stellate cells to NK cell killing via upregulation of NK cell activating ligand RAE1

Hepatic stellate cells (HSCs) store 75% of the body's supply of vitamin A (retinol) and play a key role in liver fibrogenesis. During liver injury, HSCs become activated and susceptible to natural killer (NK) cell killing due to increased expression of the NK cell activating ligand retinoic acid early inducible gene 1 (RAE-1). To study the mechanism by which RAE-1 is upregulated in HSCs during activation, an in vitro model of cultured mouse HSCs was employed. RAE-1 was detected at low levels in quiescent HSCs but upregulated in 4- and 7-day cultured HSCs (early activated HSCs), whereas 21-day cultured HSCs (fully activated HSCs) lost RAE-1 expression. High levels of RAE-1 in 4- and 7-day cultured HSCs correlated with their susceptibility to NK cell killing, which was diminished by treatment with RAE-1 neutralizing antibody. Furthermore, retinoic acid (RA) and retinal dehydrogenase (Raldh) levels were upregulated in early activated HSCs compared with quiescent or fully activated HSCs. Blocking RA synthesis by the Raldh inhibitor or blocking RA signaling by the retinoic acid receptor antagonist abolished upregulation of RAE-1 whereas treatment with RA induced RAE-1 expression in HSCs. In conclusion, during activation, HSCs lose retinol, which is either secreted out or oxidized into RA; the latter stimulates RAE-1 expression and sensitizes early activated HSCs to NK cell killing. In contrast, fully activated HSCs become resistant to NK cell killing because of lack of RAE1 expression, leading to chronic liver fibrosis and disease.

Liver fibrosis and chronic viral hepatitis

Liver fibrosis results from chronic damage to the liver in conjunction with the progressive accumulation of fibrillar extracellular matrix proteins. Fibrosis progression in patients with chronic viral hepatitis is a dynamic process where hepatic stellate cells, the most important contributor cell type, respond to a variety of host genetic factors and viral proteins. The abuse of alcohol, superimposed fatty liver disease, and age at the time of viral infection are some of the factors that accelerate liver fibrosis. Liver biopsy remains the gold standard to diagnose fibrosis and significant advances have been made to develop noninvasive markers for liver fibrosis.

Grey scale enhancement by a new self-made contrast agent in early cirrhotic stage of rabbit liver

Background

The development of new ultrasound contrast agents (UCAs) has become one of the most promising fields in ultrasound medicine. This paper evaluates a new self-made contrast agent enhancement effect developed to study the fibrotic stages of the liver in perfusion models in vivo.

Methods

We constructed experimental models of hepatic fibrosis involving five stages from F0 to F4 via administration of CCL₄ (0.01 ml/kg BW) every 3 days for 3 months. The intrahepatic circulatory time of the contrast agent was analyzed via an image and Cine-loop display. Calculations of the perfusion-related parameters including the peak signal intensity (PSI) and peak signal intensity time (PIT) of the portal vein and parenchyma were obtained from an analysis of the time-acoustic intensity curve.

Results

Hepatic artery to vein transmit time (HA-HVTT) was significantly shorter at F4 stage (mean 5.1 seconds) compared with those in other stages (mean 8.3 s, 7.5 s, 6.9 s, 6.6 s, P < 0.01). The average PSI difference of PV-parenchyma was 13.62 dB in F4 stage, demonstrating significant differences between F4 stage and other early stages (P < 0.001).

Conclusion

These results indicate that the new self-made contrast agent is capable of indicating intrahepatic hemodynamic changes. HA-HVTT and the PSI difference of the microbubble perfusion in liver parenchyma and PV were considered to differentiate the degree of hepatic fibrosis between F4 and other early stages.

Neuropsychological function in Greek patients with chronic hepatitis C

BACKGROUND

Research has shown that hepatitis C virus (HCV) infection is associated with subclinical neuropsychological deficits in the absence of hepatic encephalopathy.

METHODS

The current study assessed 32 Greek HCV patients without hepatic encephalopathy using standardized neuropsychological measures and compared them with 20 healthy controls and 29 hepatitis B virus (HBV)-infected patients. Patients and controls did not differ on age, educational level, depression or fatigue severity. Moreover, strict criteria were used to exclude any risk factor for cognitive impairment.

RESULTS

Chronic HCV patients performed significantly worse than healthy controls on verbal learning and memory (P=0.029). However, hepatitis C and hepatitis B patients were similarly impaired in cognitive function, suggesting that the observed abnormalities are not HCV specific. HCV patients' cognitive capacity was further associated with liver disease severity as indicated by fibrosis stage (r=-0.602, P=0.011). In contrast, cognitive decline did not correlate with patients' psychological distress, indicating that biological mechanisms might be implicated in its pathogenesis. Finally, after controlling for age and educational level, cirrhotic and non-cirrhotic patients appeared to be equally impaired.

CONCLUSIONS

In conclusion, this study confirmed previous findings and added further to the existing literature concerning the negative influence of HCV infection on cognition.

Effects and mechanisms of extract from Paeonia lactiflora and Astragalus membranaceus on liver fibrosis induced by carbon tetrachloride in rats

Paeonia lactiflora and Astragalus membranaceus are two popular traditional Chinese medicines, commonly used in Chinese herb prescription to treat liver disease. The extract prepared from the roots of Paeonia lactiflora and Astragalus membranaceus (PAE) demonstrated more excellent hepato-protective activity than the single herbs used individually as indicated in our preliminary studies. The present study was carried out to investigate the effects of PAE on liver fibrosis in rats induced by carbon tetrachloride (CCl(4)) and to explore its possible mechanisms. Liver fibrosis was induced in male Sprague-Dawley rats by injection with 50% CCl(4) subcutaneously twice a week for 8 weeks. At the same time, PAE (40, 80 and 160 mg/kg) was administered intragastrically. Upon pathological examination, the PAE-treated rats significantly reduced the liver damage and the symptoms of liver fibrosis. Administration of PAE decreased CCl(4)-induced elevation of serum transaminase activities, hyaluronic acid, laminin and procollagen type III levels, and contents of hydroxyproline in liver tissue by approximately 30-60%. It also restored the decrease in SOD and GSH-Px activities and inhibited the formation of lipid peroxidative products during CCl(4) treatment. Moreover, PAE (80, 160 mg/kg, ig) decreased the elevation of TGF-beta1 by 47.7% and 53.1%, respectively. In the primary cultured hepatic stellate cells (HSCs), PAE also significantly decreased [(3)H] thymidine incorporation in cells stimulated with platelet-derived growth factor-B subunit homodimer (PDGF-BB) and suppressed [(3)H] proline incorporation. These results suggested that PAE significantly inhibited the progression of hepatic fibrosis induced by CCl(4), and the inhibitory effect of PAE on hepatic fibrosis might be associated with its ability to scavenge free radicals, decrease the level of TGF-beta1 and inhibit collagen synthesis and proliferation in HSCs.