Serum α-SMA is a potential noninvasive biomarker of liver fibrosis.

The severity of fibrosis is central to the therapeutic course for patients with chronic liver disease; therefore, early detection of liver fibrosis is critical for timely therapeutic interventions. Liver biopsy is the gold standard for the diagnosis of liver fibrosis; however, it is contraindicated in several pathological conditions. Activated hepatic stellate cells (HSCs) are the main cells for fibrotic tissue synthesis, such as that of alpha-smooth muscle actin (α-SMA). This study aimed to determine whether serum α-SMA levels are a suitable noninvasive, sensitive, and reliable liver fibrosis marker. Fibrosis was induced in male Wistar rats via chronic CCl4 administration. Fibrosis was determined in the liver tissues by quantifying the hydroxyproline content and visualized using Masson's trichrome staining. Rats chronically administered CCl4 exhibited a progressive increment in the hepatic collagen content, as well as both hepatic and serum α-SMA levels in a time-dependent manner. Moreover, serum levels of α-SMA significantly correlated with hepatic α-SMA levels (p ≤ 0.001), as well as with the severity of liver fibrosis (p ≤ 0.001). These findings suggest that increased levels of serum α-SMA can be considered a potential reliable and noninvasive biomarker for early liver fibrosis.

Identification of ABCC3 and its isoforms as potential biomarker in hepatocellular carcinoma.

Liver diseases preceding the occurrence of hepatocellular carcinoma (HCC) play a crucial role in the progression and establishment of HCC, a malignancy ranked as the third deadliest cancer worldwide. Late diagnosis, alongside ineffective treatment, leads patients to a poor survival rate. This scenario argues for seeking novel alternatives for detecting liver alterations preceding the early occurrence of HCC. Experimental studies have reported that ABCC3 protein increases within HCC tumors but not in adjacent tissue. Therefore, we analyzed ABCC3 expression in public databases and investigated the presence of ABCC3 and its isoforms in plasma, urine and its release in extracellular vesicles (EVs) cargo from patients bearing cirrhosis and HCC. The UALCAN and GEPIA databases were used to analyze the expression of ABCC3 in HCC. The results were validated in a case-control study including 41 individuals bearing cirrhosis and HCC, and the levels of ABCC3 in plasma and urine samples, as well as EVs, were analyzed by ELISA and western blot. Our data showed that ABCC3 expression was higher in HCC tissues than in normal tissues and correlated with HCC grade and stage. ABCC3 protein levels were highly increased in both plasma and urine and correlated with liver disease progression and severity. The isoforms MRP3A and MRP3B of ABCC3 were significantly increased in both EVs and plasma/urine of patients bearing HCC. ABCC3 expression gradually increases in HCC tissues, and its protein levels are increased in both plasma and urine of patients with cirrhosis and HCC. MRP3A and MRP3B isoforms have the potential to be prognostic biomarkers of HCC.

The antioxidant and anti-inflammatory activities of caffeine effectively attenuate nonalcoholic steatohepatitis and thioacetamide-induced hepatic injury in male rats.

The antioxidant effect of caffeine, associated with its ability to upregulate the nuclear factor-E2-related factor-2 (Nrf2)-signaling pathway, was explored as a possible mechanism for the attenuation of liver damage. Nonalcoholic steatohepatitis (NASH) was induced in rats by the administration of a high-fat, high-sucrose, high-cholesterol diet (HFSCD) for 15 weeks. Liver damage was induced in rats by intraperitoneal administration of thioacetamide (TAA) for six weeks. Caffeine was administered orally at a daily dose of 50 mg/kg body weight during the period of NASH induction to evaluate its ability to prevent disease development. Meanwhile, rats received TAA for three weeks, after which 50 mg/kg caffeine was administered daily for three weeks with TAA to evaluate its capacity to interfere with the progression of hepatic injury. HFSCD administration induced hepatic steatosis, decreased Nrf2 levels, increased oxidative stress, induced the activation of nuclear factor-κB (NF-κB), and elevated proinflammatory cytokine levels, leading to hepatic damage. TAA administration produced similar effects, excluding steatosis. Caffeine increased Nrf2 levels; attenuated oxidative stress markers, including malondialdehyde and 4-hydroxynonenal; restored normal, reduced glutathione levels; and reduced NF-κB activation, inflammatory cytokine levels, and damage. Our findings suggest that caffeine may be useful in the treatment of human liver diseases.

Activation of the NLRP3 inflammasome by CCl4 exacerbates hepatopathogenic diet-induced experimental NASH.

INTRODUCTION AND OBJECTIVES: Administration of carbon tetrachloride (CCl4), along with an hepatopathogenic diet, is widely employed as a chemical inducer to replicate human nonalcoholic steatohepatitis (NASH) in rodents; however, the role of the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome in this model remains unclear. We aimed to determine the relevance of NLRP3 inflammasome activation in the development of NASH induced by CCl4 along with an hepatopathogenic diet in male Wistar rats. MATERIALS AND METHODS: Animals were fed either a high fat, sucrose, and cholesterol diet (HFSCD) or a HFSCD plus intraperitoneal injections of low doses of CCl4 (400 mg/kg) once a week for 15 weeks. Liver steatosis, inflammation, fibrosis, and NLRP3 inflammasome activation were evaluated using biochemical, histological, ultrastructural, and immunofluorescence analyses, western blotting, and immunohistochemistry. RESULTS: Our experimental model reproduced several aspects of the human NASH pathophysiology. NLRP3 inflammasome activation was induced by the combined effect of HFSCD plus CCl4 and significantly increased levels of both proinflammatory and profibrogenic cytokines and collagen deposition in the liver; thus, NASH severity was higher in the HFSCD+CCl4 group than that in the HFSCD group, to which CCl4 was not administered. Hepatic stellate cells, the most profibrogenic cells, were activated by HFSCD plus CCl4, as indicated by elevated levels of α-smooth muscle actin. Thus, activation of the NLRP3 inflammasome, triggered by low doses of CCl4, exacerbates the severity of NASH. CONCLUSIONS: Our results indicate that NLRP3 inflammasome activation plays a key role and may be an important therapeutic target for NASH treatment.

Caffeine mitigates experimental nonalcoholic steatohepatitis and the progression of thioacetamide-induced liver fibrosis by blocking the MAPK and TGF-ß/Smad3 signaling pathways.

INTRODUCTION AND OBJECTIVES: Caffeine consumption is associated with beneficial effects on hepatic disorders. The objectives of this study were to evaluate the antifibrotic effects of caffeine on experimental nonalcoholic steatohepatitis (NASH) induced with a high-fat, high-sucrose, high-cholesterol diet (HFSCD), as well as to evaluate the ability of caffeine to prevent the progression of experimental liver fibrosis induced by the administration of thioacetamide (TAA) in rats and explore the mechanisms of action. METHODS: NASH and fibrosis were induced in rats by the administration of an HFSCD for 15 weeks, and liver fibrosis was induced by intraperitoneal administration of 200 mg/kg TAA 3 times per week, for 6 weeks. Caffeine was administered at a dose of 50 mg/kg body weight. The effects of diet, TAA, and caffeine on fibrosis were evaluated by biochemical and histological examinations. The profibrotic pathways were analyzed by western blotting and immunohistochemistry. RESULTS: Rats exhibited liver fibrosis after HFSCD feeding and the administration of TAA. Caffeine could reduce the hepatic level of collagen and the fibrotic area in the liver. Caffeine prevented the progression of liver fibrosis by decreasing transforming growth factor-beta (TGF-ß), connective tissue growth factor (CTGF), and alpha-smooth muscle actin (α-SMA) expression and by inhibiting the activation of mitogen-activated protein kinases (MAPKs) and Smad3 phosphorylation. CONCLUSIONS: Caffeine attenuates NASH and the progression of liver fibrosis due to its antifibrotic effects and modulating the MAPK and TGF-ß pathways. Therefore, caffeine could be a suitable candidate for treating liver diseases associated with fibrosis.

Caffeine Inhibits NLRP3 Inflammasome Activation by Downregulating TLR4/MAPK/NF-κB Signaling Pathway in an Experimental NASH Model.

Caffeine elicits protective effects against liver diseases, such as NASH; however, its mechanism of action involving the pyrin domain-containing-3 (NLRP3) inflammasome signaling pathway remains to be elucidated. This study aimed to evaluate the effect of caffeine on the NLRP3 inflammasome signaling pathway in a rat model of NASH. NASH was induced by feeding rats a high-fat, -sucrose, and -cholesterol diet (HFSCD) for 15 weeks along with a weekly low dose (400 mg/kg, i.p.) of CCl4. Caffeine was administered at 50 mg/kg p.o. The effects of HFSCD+CCl4 and caffeine on the liver were evaluated using biochemical, ultrastructural, histological, and molecular biological approaches. The HFSCD+CCl4-treated rats showed fat accumulation in the liver, elevated levels of inflammatory mediators, NLRP3 inflammasome activation, antioxidant dysregulation, and liver fibrosis. Caffeine reduced necrosis, cholestasis, oxidative stress, and fibrosis. Caffeine exhibited anti-inflammatory effects by attenuating NLRP3 inflammasome activation. Moreover, caffeine prevented increases in toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) protein levels and mitigated the phosphorylation of mitogen-activated protein kinase (MAPK). Importantly, caffeine prevented the activation of hepatic stellate cells. This study is the first to report that caffeine ameliorates NASH by inhibiting NLRP3 inflammasome activation through the suppression of the TLR4/MAPK/NF-κB signaling pathway.

Days of symptoms and days of hospital admission before surgery do not influence the results of cholecystectomy in moderate acute calculous cholecystitis-Cholecystectomy remains the best treatment.

BACKGROUND AND AIMS: early cholecystectomy is the gold-standard treatment for acute calculous cholecystitis (ACC), although many surgeons still prefer delayed cholecystectomy for grade II to avoid surgical complications. The aim of this study was to analyze the postoperative morbidity and mortality of Tokyo Guidelines grade-II ACC as treated with cholecystectomy, taking into account the days of symptoms and days since hospital admission. MATERIALS AND METHODS: a unicenter, retrospective study was performed based on a prospective database. Patients with grade-II ACC treated with cholecystectomy were selected. Patients were analyzed according to days of symptoms (DS) and days of hospital admission (DHA) until cholecystectomy. Patients were subdivided into 3 groups: < 3 days, 3-5 days, and > 5 days. Univariate and multivariate analyses were performed for morbidity and mortality. Categorical variables were compared using the Chi-squared or Fischer's exact test. Continuous variables were compared using the Mann-Whitney U-test. The level of statistical significance was set at p < 0.05. RESULTS: a total of 998 patients with ACC diagnosis were included; 567 with grade-II ACC and 368 treated with cholecystectomy. Nearly 90 % were treated laparoscopically and 48.1 % underwent surgery the same day of emergency admission. With regard to DS and DHA, there were no statistical differences for severe postoperative complications, although a greater number of complications were detected in the > 5 DS group (p: 0.32) and > 5 DHA group (p: 0.00). Statistically significant differences were found in DS for mortality (p: 0.04). Postoperative length of stay was longer for > 5 DHA group cholecystectomies (p > 0.05). There were no differences with regard to hospital readmission. CONCLUSION: with regard to DS or DHA until cholecystectomy, there were no statistically significant differences related to severe postoperative complications, length of stay, or mortality.

A new minimally invasive porcine model for the study of intrahepatic bile duct dilatation.

BACKGROUND: Endoscopic ultrasound (EUS) procedures are becoming more frequent nowadays and novel techniques are on the rise. These procedures require high technical experience and complex endoscopic skills. The goal of this study was to develop a new minimally invasive animal model of bile duct dilatation in the pig, in order to offer a new tool for endoscopic and surgical therapy training and to test new therapeutic strategies. METHODS: Twenty-five female pigs underwent laparoscopic surgery in order to perform a common hepatic duct ligation. A pre- and postoperative biochemical analyses were performed: glucose, albumin, total bilirubin (TBil), gamma glutamyl transferase (GGT), alkaline phosphatase, and alanine aminotransferase were measured. Surgical time and intra- and postoperative complications were registered. Five to six days after surgery, an EUS was performed to measure intrahepatic duct size (mm). Distance from the bile duct to the EUS transductor was also recorded (mm). T-student for quantitative variables was applied. Statistical significance was defined as p value ≤ 0.05. RESULTS: The mean surgical time was 29.5 ± 14.9 min. In five pigs (20%), some mild intraoperative problems occurred. A severe postoperative complication occurred in one animal (4%). No postoperative mortality was registered. Postoperative serum analyses showed an increase in total bilirubin (p = 0.005) and gamma glutamyl transferase levels (p = 0.001). Postoperative EUS showed dilatation of the intrahepatic bile duct in 76% of pigs, with a mean diameter of 9.6 ± 3.6 mm (distance from the gastric wall of 17.0 ± 6.4 mm). CONCLUSION: The surgical procedure described here is a safe technique to induce dilatation of the intrahepatic bile ducts in the pig, with a minimally invasive approach and a high efficacy rate. This animal model might be useful for EUS techniques training and for evaluating new therapeutic approaches.

Fructose and the Liver.

Chronic diseases represent a major challenge in world health. Metabolic syndrome is a constellation of disturbances affecting several organs, and it has been proposed to be a liver-centered condition. Fructose overconsumption may result in insulin resistance, oxidative stress, inflammation, elevated uric acid levels, increased blood pressure, and increased triglyceride concentrations in both the blood and liver. Non-alcoholic fatty liver disease (NAFLD) is a term widely used to describe excessive fatty infiltration in the liver in the absence of alcohol, autoimmune disorders, or viral hepatitis; it is attributed to obesity, high sugar and fat consumption, and sedentarism. If untreated, NAFLD can progress to nonalcoholic steatohepatitis (NASH), characterized by inflammation and mild fibrosis in addition to fat infiltration and, eventually, advanced scar tissue deposition, cirrhosis, and finally liver cancer, which constitutes the culmination of the disease. Notably, fructose is recognized as a major mediator of NAFLD, as a significant correlation between fructose intake and the degree of inflammation and fibrosis has been found in preclinical and clinical studies. Moreover, fructose is a risk factor for liver cancer development. Interestingly, fructose induces a number of proinflammatory, fibrogenic, and oncogenic signaling pathways that explain its deleterious effects in the body, especially in the liver.

Curcumin downregulates Smad pathways and reduces hepatic stellate cells activation in experimental fibrosis.

INTRODUCTION AND OBJECTIVES: Curcumin, a polyphenol, is a natural compound that has been widely studied as a hepatoprotector; however, only a few studies have examined its ability to reduce fibrosis in previously established cirrhosis. The objective of this study was to investigate whether curcumin could reduce carbon tetrachloride (CCl4)-induced fibrosis and if so, to determine the action mechanisms involved in the reduction process. MATERIALS AND METHODS: CCl4 was administered to male Wistar rats (400 mg/kg, three times a week, i. p.) for 12 weeks; curcumin (100 mg/kg body weight twice per day, p. o.) was administered from week 9-12 of CCl4 treatment. Biochemical markers of hepatic injury and oxidative stress were evaluated. Hematoxylin and eosin, Masson's trichrome stains, transmission electron microscopy; immunohistochemistry, and zymography assays were carried out. Moreover, Smad3 and α-SMA mRNA and protein levels were studied. Western blotting by TGF-ß, CTGF, Col-I, MMP-13, NF-κB, IL-1, IL-10, Smad7, pSmad3, and pJNK proteins was developed. RESULTS AND CONCLUSIONS: Curcumin reduced liver damage, oxidative stress, fibrosis, and restored normal activity of MMP-9 and MMP-2. Besides, curcumin restored NF-κB, IL-1, IL-10, TGF-ß, CTGF, Col-I, MMP-13, and Smad7 protein levels. On the other hand, curcumin decreased JNK and Smad3 phosphorylation. Furthermore, curcumin treatment decreased α-SMA and Smad3 protein and mRNA levels. Curcumin normalized GSH, and NF-κB, JNK-Smad3, and TGF-ß-Smad3 pathways, leading to a decrement in activated hepatic stellate cells, thereby producing its antifibrotic effects.

Free radicals, antioxidants, nuclear factor-E2-related factor-2 and liver damage.

Oxidative/nitrosative stress is proposed to be a critical factor in various diseases, including liver pathologies. Antioxidants derived from medicinal plants have been studied extensively and are relevant to many illnesses, including liver diseases. Several hepatic disorders, such as viral hepatitis and alcoholic or nonalcoholic steatohepatitis, involve free radicals/oxidative stress as agents that cause or at least exacerbate liver injury, which can result in chronic liver diseases, such as liver fibrosis, cirrhosis and end-stage hepatocellular carcinoma. In this scenario, nuclear factor-E2-related factor-2 (Nrf2) appears to be an essential factor to counteract or attenuate oxidative or nitrosative stress in hepatic cells. In fact, a growing body of evidence indicates that Nrf2 plays complex and multicellular roles in hepatic inflammation, fibrosis, hepatocarcinogenesis and regeneration via the induction of its target genes. Inflammation is the most common feature of chronic liver diseases, triggering fibrosis, cirrhosis and hepatocellular carcinoma. Increasing evidence indicates that Nrf2 counteracts the proinflammatory process by modulating the recruitment of inflammatory cells and inducing the endogenous antioxidant response of the cell. In this review, the interactions between antioxidant and inflammatory molecular pathways are analyzed.

Stevia prevents experimental cirrhosis by reducing hepatic myofibroblasts and modulating molecular profibrotic pathways.

AIM: The aims of the present study were to investigate the capacity of stevia leaves to prevent experimental cirrhosis induced by chronic administration of carbon tetrachloride (CCl4 ) in rats and to explore the action mechanism involved. METHODS: Liver cirrhosis was established by CCl4 treatment (400 mg/kg i.p. three times a week for 12 weeks); stevia powder was administered (100 mg/kg by gavage daily) during the CCl4 treatment. Serum markers of liver damage and hydroxyproline were evaluated and histopathological analyses were carried out. The profibrotic pathways were analyzed by western blot and immunohistochemistry. RESULTS: We found for the first time that stevia cotreatment prevented the elevation of serum markers of necrosis and cholestasis and the occurrence of liver fibrosis. It is worth noting that stevia downregulated several profibrogenic pathways, including the reduction of hepatic myofibroblasts and decreased matrix metalloproteinase (MMP)2 and MMP13 expression, thereby blocking the liberation of transforming growth factor-ß from the extracellular matrix. Notably, stevia reduced the phosphorylation of pSmad3L, the most profibrogenic and mitogenic Smad, by inhibiting the activation of c-Jun N-terminal kinase and extracellular signal-regulated kinase. Interestingly, Smad7, an important antifibrotic molecule, was upregulated by stevia treatment in cirrhotic rats. These multitarget mechanisms led to the prevention of experimental cirrhosis. CONCLUSIONS: Because stevia possesses a reasonable safety profile, our results indicate that it could be useful in the clinical setting to treat chronic liver diseases.

An aqueous extract of Stevia rebaudiana variety Morita II prevents liver damage in a rat model of cirrhosis that mimics the human disease.

INTRODUCTION AND AIM: Stevia has exhibited antioxidant, antihyperglycemic, antihypertensive and anti-inflammatory properties in several in vivo and in vitro models. The objective of this study was to investigate the ability of an aqueous extract of stevia (AES) to prevent experimental cirrhosis in rats and to explore its mechanism of action. MATERIALS AND METHODS: Liver cirrhosis was induced by administering carbon tetrachloride (CCl4) (400mg/kg by i.p. injection 3 times a week for 12 weeks); AES was administered (100mg/kg by gavage daily) during the CCl4 treatment. Fibrosis was evaluated with histological, biochemical and molecular approaches, and liver damage was assessed with standardized procedures. The profibrotic pathways were analyzed by western blotting, qRT-PCR and immunohistochemistry. RESULTS AND CONCLUSIONS: Chronic CCl4 administration increased nuclear factor kappa B (NF-κB) and proinflammatory cytokine production as well as oxidative parameters such as lipid peroxidation and 4-hydroxynonenal levels, whereas GSH and nuclear factor-E2-related factor 2 (Nrf2) levels were decreased. CCl4 induced profibrogenic mediator expression, hepatic stellate cell (HSC) activation and, consequently, extracellular matrix production. AES exhibited antioxidant, anti-inflammatory and antifibrotic properties, probably because of its capacity to induce Nrf2 expression, reduce NF-κB expression and block several profibrogenic signaling pathways, subsequently inhibiting HSC activation and preventing fibrosis induced by chronic CCl4 administration.

Rebaudioside A administration prevents experimental liver fibrosis: an in vivo and in vitro study of the mechanisms of action involved.

Rebaudioside A (Reb A) is a diterpenoid isolated from the leaves of Stevia rebaudiana (Bertoni) that has been shown to possess pharmacological activity, including anti-inflammatory and antioxidant properties. However, the ability of Reb A to prevent liver injury has not been evaluated. Therefore, we aimed to study the potential of Reb A (20 mg/kg; two times daily intraperitoneally) to prevent liver injury induced by thioacetamide (TAA) administration (200 mg/kg; three times per week intraperitoneally). In addition, cocultures were incubated with either lipopolysaccharide or ethanol. Antifibrotic, antioxidant and immunological responses were evaluated. Chronic TAA administration produced considerable liver damage and distorted the liver parenchyma with the presence of prominent thick bands of collagen. In addition, TAA upregulated the expression of α-smooth muscle actin, transforming growth factor-ß1, metalloproteinases 9, 2 and 13, and nuclear factor kappaB and downregulated nuclear erythroid factor 2. Reb A administration prevented all of these changes. In cocultured cells, Reb A prevented the upregulation of genes implicated in fibrotic and inflammatory processes when cells were exposed to ethanol and lipopolysaccharide. Altogether, our results suggest that Reb A prevents liver damage by blocking oxidative processes via upregulation of nuclear erythroid factor 2, exerts immunomodulatory effects by downregulating the nuclear factor-κB system and acts as an antifibrotic agent by maintaining collagen content.

Failure to perform index cholecystectomy during acute cholecystitis results in significant morbidity for patients who present with recurrence.

BACKGROUND: Although index cholecystectomy is considered the treatment of choice for acute cholecystitis (AC), many hospital systems struggle to provide such a service. The aim of this study was to analyze the effect of failure to perform index cholecystectomy in patients presenting with acute cholecystitis. METHODS: Between June 2010 and December 2015, all patients presenting to one hospital with an initial attack of AC were enrolled into a prospective database. Patient's records were reviewed up until point of delayed cholecystectomy or for a minimum of 24 months after the initial presentation with AC. Recurrent AC was defined as early (<6 weeks from initial discharge) or late (>6 weeks from initial discharge). RESULTS: In total 998 patients presented with AC, 409 (41%) of whom were discharged without index cholecystectomy. Eighty-three (20%) patients presented with AC recurrence (ACR). Compared to the first AC episode, patients were more likely to present with grade III AC and suffer significantly greater morbidity (p < 0.05 for all comparisons). A prior history of biliary disease was associated with ACR (p = 0.002). ACR occurred early in 48 (58%) patients and delayed in 35 (42%) patients. CONCLUSIONS: Twenty percent of patients discharged without cholecystectomy after their first attack of ACR will develop recurrence within the first two years. Half of ACR will occur within 6 weeks. Patients who present with ACR are more likely to develop more severe AC and are likely to suffer greater morbidity as compared to their first attack.

Stevia rebaudiana tea prevents experimental cirrhosis via regulation of NF-κB, Nrf2, transforming growth factor beta, Smad7, and hepatic stellate cell activation.

Stevia has been shown to prevent oxidative stress and inflammation in carbon tetrachloride­induced cirrhosis models. This study aimed to investigate the ability of an aqueous extract of stevia (AES) to prevent thioacetamide (TAA)­induced cirrhosis in rats and to explore its mechanism of action. Liver cirrhosis was established by administering TAA (200 mg/kg by i.p. injections three times a week for 10 weeks); AES was administered (100 mg/kg by gavage daily) during the TAA treatment. Liver damage and fibrosis were evaluated, and the profibrotic pathways were analyzed by western blotting and immunohistochemistry. TAA increased nuclear factor kappa B (NF­κB) and pro­inflammatory cytokine production, as well as the malondialdehyde and 4­hydroxynonenal levels, whereas the glutathione/glutathione disulfide and nuclear factor­E2­related factor 2 (Nrf2) levels were decreased. Moreover, TAA increased collagen production, hepatic stellate cell (HSC) activation, and expression of profibrogenic mediators. TAA­treated rats that had been exposed to Mn2+ exhibited altered striatal dopamine turnover, indicating hepatic encephalopathy. AES partially or completely prevented all of these effects. AES showed antioxidant, anti­inflammatory, and antifibrotic properties, probably because of its capacity to induce Nrf2 expression, reduce NF­κB expression, and block several profibrogenic signaling pathways, subsequently inhibiting HSC activation and preventing fibrosis and dopamine turnover.

Redox state and methods to evaluate oxidative stress in liver damage: From bench to bedside.

 Oxidative stress is importantly involved in the pathophysiology of various liver diseases. The redox state participates on the course of the inflammatory, metabolic and proliferative liver diseases. The main sources of the reactive oxygen species (ROS) are represented by the mitochondria and cytochrome P450 enzymes in the hepatocyte, Kupffer cells and neutrophils. Cells are provided with efficient molecular strategies to strictly control the intracellular ROS level and to maintain the balance between oxidant and antioxidant molecules. Hepatocyte's proteins, lipids and DNA are among the cellular structures to be affected primarily by ROS and reactive nitrogen species (RNS). This process disrupts at cellular and molecular level the structure-function relationship on liver cells at different sites. Therefore, further studies on the molecular mechanisms of the oxidative stress pathways on liver diseases are urgently required, because they could explain the pathogenesis of various liver disorders. Moreover, new methods to evaluate oxidative stress like the oxidative markers among hepatocytes offers the potential to diagnose the degree of liver injury and ultimately to assess the response to pharmacological therapies. In this review, we discuss the molecular, metabolic and aging aspects of the oxidative stress, and the methods to evaluate oxidative stress on liver damage.

Hesperidin prevents liver fibrosis in rats by decreasing the expression of nuclear factor-κB, transforming growth factor-ß and connective tissue growth factor.

BACKGROUND/AIMS: To evaluate the antioxidant, immunomodulatory, antinecrotic and antifibrotic effects of hesperidin on CCl4-induced cirrhosis. METHODS: Liver damage was produced by giving CCl4 injections (0.4 g/kg, i.p., 3 times per week for 8 weeks) to rats. Hesperidin (200 mg/kg) was administered using gavage. The expression of nuclear factor-κB (NF-κB), transforming growth factor-ß (TGF-ß), connective tissue growth factor (CTGF), interleukin (IL)-10 and IL-1ß was assessed using Western blotting. Alanine aminotransferase (ALT) and γ-glutamyl transpeptidase (γ-GTP) serum activities, glycogen content, reduced/oxidised glutathione (GSH/GSSG) ratio, lipid peroxidation degree and fibrosis (using hydroxyproline content and a histopathological analysis) were measured. RESULTS: CCl4 increased the enzymatic activities of ALT and γ-GTP, liver lipid peroxidation, the hydroxyproline content as well as NF-κB, TGF-ß, CTGF, IL-1ß and IL-10 levels and decreased the glycogen content and GSH/GSSG ratio. Hesperidin significantly decreased the modifications produced by CCl4, except in the case of IL-10, which was further increased by the flavone. The group receiving hesperidin alone showed decreases in lipid peroxidation, NF-κB, TGF-ß, CTGF and IL-1ß and an increase in IL-10. The results of the histopathological analysis were in agreement with the biochemical and molecular findings. CONCLUSIONS: This study demonstrates that hesperidin prevents experimental necrosis and fibrosis. The action mechanism of hesperidin is associated with its ability to reduce oxidative stress and modulate proinflammatory and profibrotic signals. These results support earlier findings demonstrating the beneficial effect of hesperidin against liver damage.