Plasma Alanine Aminotransferase Levels Research Articles

Dietary fat stimulates development of NAFLD more potently than dietary fructose in Sprague\u2013Dawley rats

BackgroundIn humans and animal models, excessive intake of dietary fat, fructose and cholesterol has been linked to the development of non-alcoholic fatty liver disease (NAFLD). However, the individual roles of the dietary components remain unclear. To investigate this further, we compared the effects of a high-fat diet, a high-fructose diet and a combination diet with added cholesterol on the development of NAFLD in rats.MethodsForty male Sprague–Dawley rats were randomized into four groups receiving either a control-diet (Control: 10% fat); a high-fat diet (HFD: 60% fat, 20% carbohydrate), a high-fructose diet [HFr: 10% fat, 70% carbohydrate (mainly fructose)] or a high-fat/high-fructose/high-cholesterol-diet (NASH: 40% fat, 40% carbohydrate (mainly fructose), 2% cholesterol) for 16 weeks.ResultsAfter 16 weeks, liver histology revealed extensive steatosis and inflammation in both NASH- and HFD-fed rats, while hepatic changes in HFr-rats were much more subtle. These findings were corroborated by significantly elevated hepatic triglyceride content in both NASH- (p < 0.01) and HFD-fed rats (p < 0.0001), elevated hepatic cholesterol levels in NASH-fed rats (p < 0.0001), but no changes in HFr-fed rats, compared to Control. On the contrary, only HFr-fed rats developed dyslipidemia as characterized by higher levels of plasma triglycerides compared to all other groups (p < 0.0001). Hepatic dysfunction and inflammation was confirmed in HFD-fed rats by elevated levels of hepatic MCP-1 (p < 0.0001), TNF-alpha (p < 0.001) and plasma β-hydroxybutyrate (p < 0.0001), and in NASH-fed rats by elevated levels of hepatic MCP-1 (p < 0.01), increased hepatic macrophage infiltration (p < 0.001), and higher plasma levels of alanine aminotransferase (p < 0.0001) aspartate aminotransferase (p < 0.05), haptoglobin (p < 0.001) and TIMP-1 (p < 0.01) compared to Control.ConclusionThese findings show that dietary fat and cholesterol are the primary drivers of NAFLD development and progression in rats, while fructose mostly exerts its effect on the circulating lipid pool.

Potential effect of recombinant thrombomodulin on ischemia-reperfusion liver injury in rats.

Liver ischemia-reperfusion (I/R) injury is a severe complication of liver surgery. However, the responsible molecular mechanism remains unclear. High-mobility group box 1 (HMGB1) is released from the nuclei of cells and behaves as a damage-associated molecular pattern. The aim of this study is to reveal the roles of HMGB1 and the effects of recombinant thrombomodulin (rTM) in I/R liver injury. Rats underwent partial hepatic ischemia followed by reperfusion, and changes in HMGB1 were assessed. Recombinant thrombomodulin was used as an inhibitor of HMGB1. In rats with I/R injury, the HMGB1 level significantly decreased in the liver tissue and significantly increased in the serum after surgery (P < 0.001 for both). No difference in the HMGB1 level in the hepatocytes was observed between the rTM(-) group and rTM(+) group after surgery. Conversely, the serum HMGB1 level was significantly lower in the rTM(+) group than the rTM(-) group after surgery (P < 0.001). The levels of tumor necrosis factor-α and interleukin-6 in the liver tissue 24h after surgery were significantly lower in the rTM(+) group than the rTM(-) group (P < 0.001). The plasma alanine aminotransferase level at 24h after surgery of the rTM(+) group was significantly decreased after surgery compared with that of the rTM(-) group (P < 0.001). The necrotic area of the liver tissue 24h after surgery was significantly smaller in the rTM(+) group than the rTM(-) group (P < 0.001). Recombinant thrombomodulin can serve as a treatment for I/R liver injury by inhibiting HMGB1.

Evidence of a liver-alpha cell axis in humans: hepatic insulin resistance attenuates relationship between fasting plasma glucagon and glucagonotropic amino acids.

The secretion of glucagon is controlled by blood glucose and inappropriate secretion of glucagon contributes to hyperglycaemia in diabetes. Besides its role in glucose regulation, glucagon regulates amino acid metabolism in hepatocytes by increasing ureagenesis. Disruption of this mechanism causes hyperaminoacidaemia, which in turn increases glucagon secretion. We hypothesised that hepatic insulin resistance (secondary to hepatic steatosis) via defective glucagon signalling/glucagon resistance would lead to impaired ureagenesis and, hence, increased plasma concentrations of glucagonotropic amino acids and, subsequently, glucagon. To examine the association between glucagon and amino acids, and to explore whether this relationship was modified by hepatic insulin resistance, we studied a well-characterised cohort of 1408 individuals with normal and impaired glucose regulation. In this cohort, we have previously reported insulin resistance to be accompanied by increased plasma concentrations of glucagon. We now measure plasma levels of amino acids in the same cohort. HOMA-IR was calculated as a marker of hepatic insulin resistance. Fasting levels of glucagonotropic amino acids and glucagon were significantly and inversely associated in linear regression models (persisting after adjustment for age, sex and BMI). Increasing levels of hepatic, but not peripheral insulin resistance (p > 0.166) attenuated the association between glucagon and circulating levels of alanine, glutamine and tyrosine, and was significantly associated with hyperaminoacidaemia and hyperglucagonaemia. A doubling of the calculated glucagon-alanine index was significantly associated with a 30% increase in hepatic insulin resistance, a 7% increase in plasma alanine aminotransferase levels, and a 14% increase in plasma γ-glutamyltransferase levels. This cross-sectional study supports the existence of a liver-alpha cell axis in humans: glucagon regulates plasma levels of amino acids, which in turn feedback to regulate the secretion of glucagon. With hepatic insulin resistance, reflecting hepatic steatosis, the feedback cycle is disrupted, leading to hyperaminoacidaemia and hyperglucagonaemia. The glucagon-alanine index is suggested as a relevant marker for hepatic glucagon signalling.

Hepatoprotective effects of hexane root extract of Alchornea laxiflora in sodium arsenate toxicity in wistar albino rats

Background: Medicinal plants are have been used in the treatment of myriad disease conditions, Alchornea laxiflora is one of such medicinal plant. Aim: To investigate the hepatoprotective effect of hexane root extract of Alchornea laxiflora against sodium arsenate induced liver damage in wistar male rats. Setting and Design: Extraction and administration of bioactive extract. Materials and Methods: Extraction of air-dried ground root of Alchornea laxiflora was done by extracting 500 g with 500 cm of 95% hexane for 72 hrs.The animals (120-150 g) were pre-treated with the extract at varying doses (0.1, 0.5, 1.0, 10, 50 and 100 mg/kg body weight) for seven days orally prior to the intra-peritoneal administration of the toxicant (sodium arsenate) at a dose of 2 mg/kg body weight at the eight day. Hepatoprotective activity of the extracts was evaluated by studying the Cytochrome b5content, Glutathione-S-transferase and 4- Nitroanisole-o-demethylase activities in the liver, Plasma levels of Alanine aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatase (ALP) and the levels of Total protein, Albumin, Globulin and Glutathione of the various groups. Statistical Analysis: The data were analysed with Microsoft excels (for windows 2007) and Student t-test and ANOVA. Result and Conclusion: The results suggest that pre-treatment of rats with hexane root extract of Alchornea laxiflora for seven days reduced the elevated levels of liver enzymes, reduced the levels of induced liver metabolizing enzymes and the levels of Total protein, Albumin, Globulin and Glutathione that was increased by the toxicity of sodium arsenate in rats and as such possess hepatoprotective effect against sodium arsenate.

Hepatoprotective effect of Opuntia dillenii seed oil on CCl4 induced acute liver damage in rat

Objective: To investigate the hepatoprotective effect of Opuntia dillenii seed oil (ODSO) on CCl4 provoked liver injury in rat. Methods: Animals were treated orally with ODSO at a concentration of 2 mL/kg, once daily for one week before the first intraperitoneal injection of CCl4, and thereafter the administration of the oil was continued for 7 days until the introduction of the second injection of CCl4. Fourteen hours after the last dose of CCl4, rats were sacrificed, and the relative liver weight, weight gain, alkaline phosphatase, aspartate amino transferase, alanine aminotransferase, direct bilirubin, total bilirubin, triglycerides, total cholesterol, very low density lipoprotein, low density lipoprotein, high density lipoprotein, plasmatic glucose, urea, creatinine, acid uric and malondialdehyde were determined. Results: The significant increase was found in relative liver weight and plasma levels of alanine aminotransferase, aspartate amino transferase, alkaline phosphatase, total bilirubin, direct bilirubin, triglycerides, very low-density lipoprotein, urea, uric acid and malondialdehyde. Likewise, the significant decrease was indicated in the weight gain and the level of glucose plasmatic, and high-density lipoprotein levels in CCl4 produced liver injury in rats were re-established to normal levels when treated with ODSO. While, no change was observed in the total cholesterol, low-density lipoprotein and creatinine in all animals. Conclusions: We conclude that the ODSO has a protective effect on CCl4-mediated liver injury. Hence, we suggest its inclusion as a preventive control of liver disorders.

Sicyos angulatus ameliorates acute liver injury by inhibiting oxidative stress via upregulation of anti-oxidant enzymes

ABSTRACTObjective: We aimed to investigate the effect of Sicyos angulatus (SA) ethanolic extracts as antioxidants and potential treatments for liver disease.Methods: To establish a mouse model of liver injury, C57BL/6 male mice were injected via the caudal vein with a single dose of concanavalin A (Con A, 15 mg kg−1). SA extracts were administered once by oral gavage 30 min before Con A injection.Results: In vitro studies showed that SA decreased tert-butyl hydroperoxide (t-BHP)-induced reactive oxygen species (ROS) production. SA administration reduced plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as well as hepatic ROS levels, in a dose-dependent manner. Moreover, SA increased the activities of the hepatic antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase in a dose-dependent manner. Furthermore, SA treatment reduced pro-apoptotic protein levels. Con A-mediated cytosolic release of Smac/DIABLO and apoptosis-inducing factor (AIF), which are markers of necrosis, were dramatically decreased in HepG2 cells treated with SA.Conclusion: SA ameliorated liver injury and might be a good strategy for the treatment of liver injury.

Investigation of pharmacological responses to anti-diabetic drugs in female Spontaneously Diabetic Torii (SDT) fatty rats, a new nonalcoholic steatohepatitis (NASH) model.

Nonalcoholic steatohepatitis (NASH) is a progressive liver disease, and some patients develop hepatic cirrhosis/carcinoma. Animal models play key roles in the development of new therapies for NASH. In this study, the pharmacological effects of metformin and pioglitazone were investigated in female Spontaneously Diabetic Torii (SDT) fatty rats to verify the utility of this model. The anti-diabetic drugs were administered to SDT fatty rats fed a cholesterol-enriched diet from 4 to 25 weeks, and changes in food intake, body weight, and blood chemistry parameters were evaluated every 4 weeks. The hepatic lipid content, mRNA expression in relation to lipid synthesis, inflammation, and fibrosis, and histopathological analyses were performed at 25 weeks. Pioglitazone improved hyperglycemia, hyperlipidemia, and abnormalities in hepatic parameters. The insulin levels were lower than those in the control rats before 16 weeks. Plasma glucose levels in the metformin-treated rats were lower than those in the control rats, and plasma alanine aminotransferase levels temporarily decreased. The lipid content and some mRNA expression in relation to fibrosis in the liver decreased with pioglitazone treatment, and the mRNA expression of microsomal triglyceride transfer protein increased. Hepatic fibrosis observed in the SDT fatty rats improved with pioglitazone treatment; however, the effect with metformin treatment was partial. These results in both drugs are in line with results in the human study, suggesting that the SDT fatty rat is useful for developing new anti-NASH drugs that show potential to regulate glucose/lipid metabolism.

Gene Therapy with BMN 270 Results in Therapeutic Levels of FVIII in Mice and Primates and Normalization of Bleeding in Hemophilic Mice.

Hemophilia A is an X-linked bleeding disorder caused by mutations in the gene encoding the factor VIII (FVIII) coagulation protein. Bleeding episodes in patients are reduced by prophylactic therapy or treated acutely using recombinant or plasma-derived FVIII. We have made an adeno-associated virus 5 vector containing a B domain-deleted (BDD) FVIII gene (BMN 270) with a liver-specific promoter. BMN 270 injected into hemophilic mice resulted in a dose-dependent expression of BDD FVIII protein and a corresponding correction of bleeding time and blood loss. At the highest dose tested, complete correction was achieved. Similar corrections in bleeding were observed at approximately the same plasma levels of FVIII protein produced either endogenously by BMN 270 or following exogenous administration of recombinant BDD FVIII. No evidence of liver dysfunction or hepatocyte endoplasmic reticulum stress was observed. Comparable doses in primates produced similar levels of circulating FVIII. These preclinical data support evaluation of BMN 270 in hemophilia A patients.

Response to Pioglitazone in Patients With Nonalcoholic Steatohepatitis With vs Without Type 2 Diabetes

Pioglitazone is effective for long-term treatment of patients with nonalcoholic steatohepatitis (NASH) with prediabetes or type 2 diabetes. However, it is not clear how the presence of type 2 diabetes affects the drug's efficacy. We compared metabolic and histologic responses to pioglitazone in patients with NASH and prediabetes vs type 2 diabetes. We performed a prospective study of adults with biopsy-proven NASH (52 with type 2 diabetes and 49 with prediabetes), enrolled from the general population of San Antonio, Texas, from 2008 through 2014. After a run-in period of approximately 4 weeks, when all baseline measurements were made (liver magnetic resonance proton spectroscopy, euglycemic insulin clamp with glucose turnover measurements, dual-energy absorptiometry, and liver biopsy), subjects were randomly assigned to groups given pioglitazone or placebo (45 mg/d) for 18 months; all procedures performed at baseline were then repeated. The primary outcome was a reduction in nonalcoholic fatty liver disease activity score of 2 points or more (for at least 2 components) without worsening of fibrosis (and expressed as difference vs placebo). Secondary outcomes included NASH resolution, individual histologic components, intrahepatic triglyceride content (measured by 1H magnetic resonance spectroscopy), and insulin sensitivity (measured by euglycemic insulin clamp). The primary outcome was met by 48% of patients with type 2 diabetes vs 46% without diabetes. Resolution of NASH was achieved in 44% of patients with type 2 diabetes vs 26% without diabetes. A significant reduction in fibrosis, from baseline, was observed only in patients with type 2 diabetes (P= .035). Intrahepatic triglyceride content was reduced by 11% ± 2% in patients with diabetes vs a reduction of 9% ± 2% in patients without diabetes (P= .62); the plasma level of alanine aminotransferase was reduced by 50 ± 10 U/L in patients with diabetes vs a reduction of 36 ± 5 U/L in patients without diabetes (P= .22). Pioglitazone was associated with a significantly greater insulin sensitivity in adipose tissue of patients with diabetes vs without diabetes (P < .001), but nonsignificant differences in responses in hepatic (P= .49) and skeletal muscle (P= .32) insulin sensitivity. In a prospective study, we found pioglitazone to be effective in patients with and without type 2 diabetes. However, pioglitazone reduced liver fibrosis and increased adipose tissue insulin sensitivity at significantly greater levels in patients with type 2 diabetes than in patients with prediabetes. Further studies are needed to determine the mechanisms by which pioglitazone reduces liver disease in patients with type 2 diabetes. ClinicalTrials.gov: NCT00994682.

Subchronic bisphenol S exposure affects liver function in mice involving oxidative damage

Bisphenol S (BPS) has been widely used in the manufacturing industry as a substitute for bisphenol A (BPA). Emerging evidences, mostly from in vitro studies, suggest that BPS may exert a variety of toxicological effects and have the potential to induce oxidative stress. Nevertheless, few data are available for the in vivo effects of BPS on liver, an important target of drug toxicity. For the first time, our study systematically investigated the effects of BPS at a wide range of doses on liver function in mice upon oral administration. We found that treatment with 5000 μg/kg BPS for 8 weeks resulted in liver injury with increased plasma levels of alanine aminotransferase, aspartate aminotransferase and total bilirubin, as well as defects in hepatic morphology. Moreover, such exposure to BPS induced oxidative stress in the liver of mice by decreasing activities of antioxidant enzymes, and increasing lipid peroxidation level and expression of two biomarker genes, HO-1 and GADD45B. No significant changes were observed for treatment with lower doses (5–500 μg/kg) or shorter duration (4 weeks). In conclusion, subchronic BPS exposure could affect liver function in mice by inducing oxidative damage, indicating that BPS may be not an absolutely safe alternative to BPA.

Toxicological evaluations of aqueous extracts of two Nigerian ethnobotanicals (Tetrapleura tetraptera and Quassia undulata) of neurological importance in rats

Tetrapleura tetraptera (TT) and Quassia undulata (QU) are two predominant ethnobotanicals commonly used in traditional medical practices for the management of neurological disorders in Nigeria. However, there is a dearth of information on the toxicological aspects of these plants. Hence, in this study, a 14-day toxicological evaluation of aqueous extracts of TT and QU were carried out in rats. The extracts were administered orally with 5, 50, 500, 2000, and 5000 mg/kg body weight. Signs of toxicity were observed every hour for the first 6 h and every day for 14 days. Mortality, clinical signs, body weight changes, and biochemical parameters were monitored during the study period. There were no mortality or change in weight observed in the rats at all doses for both extracts, while some clinical signs were observed in rats dosed at 5000 mg/kg during the first 2 h of dosing. Also, there were no significant changes in the plasma liver marker enzymes [aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT)], plasma renal marker enzymes [creatinine, urea, blood urea nitrogen (BUN), and uric acid], and the tissue malondialdehyde (MDA) levels of rats administered 5, 50, 500, and 2000 mg/kg of both extracts when compared to the control, but there was a significant increase in the plasma AST, ALT, and MDA levels of rats administered 5000 mg/kg when compared to the control. The no observed adverse effects level (NOAEL) value of 5–2000 mg/kg implies that the extracts could be safe at those doses and could give some information on the safety of these plants with respect to their ethnomedicinal uses especially in the management of neurological disorder.

Evaluating mRNA Expression Levels of the TLR4/IRF5 Signaling Axis During Hepatic Ischemia-Reperfusion Injuries

Hepatic ischemia and reperfusion during liver transplant surgery result in hepatocellular damage. Toll-like receptors, especially TLR4, have a fundamental basic role in the inflammatory phase of ischemia-reperfusion injuries. The effect of the TRIF-dependent signaling pathway downstream of TLR4 in hepatic ischemia-reperfusion injury has been well established. However, the role of TLR4-MyD88-dependent signal transduction in hepatic ischemia-reperfusion injury has not yet been clarified. The interferon regulatory factor 5 was introduced as the main regulator of the TLR4-MyD88 signaling pathway for activating proinflammatory cytokines. The present study was carried out to investigate the functional impact of the TLR4/IRF5 signaling axis in hepatic ischemia-reperfusion injury. mRNA expression levels of TLR4, IRF5, tumor necrosis factor α, interleukin 1β, and interleukin 6 were measured using real-time polymerase chain reaction after short (3 h) and long (168 h) reperfusion periods in a hepatic mouse model of ischemia-reperfusion injury in the presence and absence of N-acetylcysteine. Liver damage was evaluated by plasma levels of alanine aminotrans-ferase and histopathology. Our results show that mRNA levels of TLR4/IRF5 and its downstream cytokines were significantly elevated 3 hours after reperfusion and had drastically fallen to baseline levels 168 hours after reperfusion. Plasma levels of alanine aminotransferase showed the same pattern. Histopathologic study of the samples revealed significant hepatic cell infiltration and necrosis 168 hours after reperfusion. Pretreatment with N-acetylcysteine significantly decreased the mRNA levels of TLR4/IRF5 and its downstream cytokines 3 hours after reperfusion and subsequently improved the previously mentioned hepatic damages 168 hours after reperfusion. This study suggests a possible role for the TLR4/IRF5 signaling pathway in hepatic ischemia-reperfusion injury. Furthermore, it reveals that N-acetylcysteine may suppress this inflammatory axis and consequently improve hepatic injuries.

Dietary Linoleic Acid and Its Oxidized Metabolites Exacerbate Liver Injury Caused by Ethanol via Induction of Hepatic Proinflammatory Response in Mice

Alcoholic liver disease is a major human health problem leading to significant morbidity and mortality in the United States and worldwide. Dietary fat plays an important role in alcoholic liver disease pathogenesis. Herein, we tested the hypothesis that a combination of ethanol and a diet rich in linoleic acid (LA) leads to the increased production of oxidized LA metabolites (OXLAMs), specifically 9- and 13-hydroxyoctadecadienoic acids (HODEs), which contribute to a hepatic proinflammatory response exacerbating liver injury. Mice were fed unsaturated (with a high LA content) or saturated fat diets (USF and SF, respectively) with or without ethanol for 10 days, followed by a single binge of ethanol. Compared to SF+ethanol, mice fed USF+ethanol had elevated plasma alanine transaminase levels, enhanced hepatic steatosis, oxidative stress, and inflammation. Plasma and liver levels of 9- and 13-HODEs were increased in response to USF+ethanol feeding. We demonstrated that primarily 9-HODE, but not 13-HODE, induced the expression of several proinflammatory cytokines invitro in RAW264.7 macrophages. Finally, deficiency of arachidonate 15-lipoxygenase, a major enzyme involved in LA oxidation and OXLAM production, attenuated liver injury and inflammation caused by USF+ethanol feeding but had no effect on hepatic steatosis. This study demonstrates that OXLAM-mediated induction of a proinflammatory response in macrophages is one of the potential mechanisms underlying the progression from alcohol-induced steatosis to alcoholic steatohepatitis.

Oleanolic acid derivative DKS26 exerts antidiabetic and hepatoprotective effects in diabetic mice and promotes glucagon-like peptide-1 secretion and expression in intestinal cells.

Glucagon-like peptide-1 (GLP-1) is an important target for diabetes therapy based on its key role in maintaining glucose and lipid homeostasis. This study was designed to investigate antidiabetic and hepatoprotective effects of a novel oleanolic acid derivative DKS26 in diabetic mice and elucidate its underlying GLP-1 related antidiabetic mechanisms in vitro and in vivo. The therapeutic effects of DKS26 were investigated in streptozotocin (STZ)-induced and db/db diabetic mouse models. Levels of plasma glucose, glycosylated serum protein (GSP), lipid profiles, insulin, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), oral glucose tolerance (OGT), pancreatic islets and hepatic histopathological morphology, liver lipid levels and expression of pro-inflammatory cytokines were assessed. Intestinal NCI-H716 cells and diabetic models were used to further validate its potential GLP-1-related antidiabetic mechanisms. DKS26 treatment (100mg·kg-1 ·day-1 ) decreased plasma levels of glucose, GSP, ALT and AST; ameliorated OGT and plasma lipid profiles; augmented plasma insulin levels; alleviated islets and hepatic pathological morphology; and reduced liver lipid accumulation, inflammation and necrosis in vivo. Furthermore, DKS26 enhanced GLP-1 release and expression, accompanied by elevated levels of cAMP and phosphorylated PKA in vitro and in vivo. DKS26 exerted hypoglycaemic, hypolipidaemic and islets protective effects, which were associated with an enhanced release and expression of GLP-1 mediated by the activation of the cAMP/PKA signalling pathway, and alleviated hepatic damage by reducing liver lipid levels and inflammation. These findings firmly identified DKS26 as a new viable therapeutic option for diabetes control.

Metformin reduces intrahepatic fibrosis and intrapulmonary shunts in biliary cirrhotic rats

BackgroundLiver fibrosis causes portal hypertension which dilates collateral vasculature and enhances extra-hepatic angiogenesis including intrapulmonary shunts, which subsequently complicates with hepatopulmonary syndrome. Metformin is an anti-diabetic agent which possesses anti-inflammation and anti-angiogenesis properties. This study evaluated the effect of metformin treatment on liver and lung in a non-diabetic rat model with biliary cirrhosis induced via common bile duct ligation (CBDL). MethodsCBDL rats were fed with metformin 150 mg/kg/day during the 8th–28th day post operation. The hemodynamic and biochemistry parameters were tested, and blood gas analysis was performed. The liver and lung were dissected for protein analysis and immuno-histochemical stains. Intrapulmonary shunting degree was determined using color microsphere method. ResultsMetformin treatment neither induced obvious hypoglycemic event nor altered hemodynamics in cirrhotic rats. The plasma levels of alanine aminotransferase were significantly reduced by metformin (control vs. metformin: 269 ± 56 vs. 199 ± 21 IU/L, P = 0.02). Sirius Red stains and CD-68 stains showed that metformin reduced intrahepatic fibrosis and CD-68-positive macrophages. Metformin did not influence hypoxia and intrapulmonary angiogenesis; however, it significantly reduced intrapulmonary shunts (31.7 ± 10.1 vs. 15.0 ± 6.6%, P = 0.006.). Furthermore, metformin reduced the protein expressions of COX-2 and PI3K in liver and COX-1 in lung. ConclusionMetformin reduced liver injury and improved hepatic fibrosis in cirrhotic rats. It also attenuated the intrapulmonary shunts. However, the effects of metformin on pulmonary angiogenesis and hypoxia were insignificant.

Weight-adjusted lean body mass and calf circumference are protective against obesity-associated insulin resistance and metabolic abnormalities.

BackgroundTo test the hypothesis that preserved muscle mass is protective against obesity-associated insulin resistance and metabolic abnormalities, we analyzed the relationship of lean body mass and computed tomography-assessed sectional areas of specific skeletal muscles with insulin resistance and metabolic abnormalities in a healthy cohort.MethodsA total of 195 subjects without diabetes who had completed a medical examination were included in this study. Various anthropometric indices such as circumferences of the arm, waist, hip, thigh, and calf were measured. Body composition (fat and lean body mass) was determined by bioelectrical impedance analysis. Sectional areas of specific skeletal muscles (iliopsoas, erector spinae, gluteus, femoris, and rectus abdominis muscles) were measured using computed tomography.FindingsFat and lean body mass were significantly correlated with metabolic abnormalities and insulin resistance indices. When adjusted by weight, relationships of fat and lean body mass with metabolic parameters were mirror images of each other. The weight-adjusted lean body mass negatively correlated with systolic and diastolic blood pressures; fasting plasma glucose, HbA1c, alanine aminotransferase, and triglyceride, and insulin levels; and hepatic insulin resistance indices, and positively correlated with HDL-cholesterol levels and muscle insulin sensitivity indices. Compared with weight-adjusted lean body mass, weight-adjusted sectional areas of specific skeletal muscles showed similar, but not as strong, correlations with metabolic parameters. Among anthropometric measures, the calf circumference best reflected lean body mass, and weight-adjusted calf circumference negatively correlated with metabolic abnormalities and insulin resistance indices.InterpretationWeight-adjusted lean body mass and skeletal muscle area are protective against weight-associated insulin resistance and metabolic abnormalities. The calf circumference reflects lean body mass and may be useful as a protective marker against obesity-associated metabolic abnormalities.

Liver Safety of Statins in Prediabetes or T2DM and Nonalcoholic Steatohepatitis: Post Hoc Analysis of a Randomized Trial.

Patients with nonalcoholic fatty liver disease have a high cardiovascular risk, but statins are rarely prescribed because of fear of hepatotoxicity. To prospectively assess the long-term safety of statins in patients with prediabetes/type 2 diabetes mellitus (T2DM) and nonalcoholic steatohepatitis (NASH). Post hoc analysis of statin use during a randomized, controlled trial assessing pioglitazone vs placebo for NASH. A total of 101 patients (86 receiving statins) with biopsy-proven NASH and prediabetes/T2DM were followed for up to 36 months. Oral glucose tolerance test and percutaneous liver biopsy (baseline, month 18, and month 36); liver magnetic resonance spectroscopy and euglycemic insulin clamp (baseline and month 18). Histologic and biochemical safety of statin use among patients with NASH. Only 37% of patients were receiving statins at enrollment despite their high cardiovascular risk. Statin nonusers had higher plasma alanine aminotransferase levels but similar histologic severity of liver disease at baseline. In both statin users and nonusers, the same number of patients (n = 4) had a twofold or greater increase in plasma aminotransferases during follow-up. One statin nonuser was discontinued from the study because of this elevation. Values returned to normal without any active measure in all other cases. No changes on liver histology or hepatic insulin resistance were observed in patients with NASH newly started on a statin and receiving placebo during the main study. Statin therapy is safe in patients with prediabetes/T2DM and NASH. Given their high cardiovascular risk, statin therapy should be encouraged in this population.

Vitamin D3-induced hypercalcemia increases carbon tetrachloride-induced hepatotoxicity through elevated oxidative stress in mice.

The aim of this study was to determine whether calcium potentiates acute carbon tetrachloride (CCl4) -induced toxicity. Elevated calcium levels were induced in mice by pre-treatment with cholecalciferol (vitamin D3; V.D3), a compound that has previously been shown to induce hypercalcemia in human and animal models. As seen previously, mice injected with CCl4 exhibited increased plasma levels of alanine aminotransferase, aspartate aminotransferase, and creatinine; transient body weight loss; and increased lipid peroxidation along with decreased total antioxidant power, glutathione, ATP, and NADPH. Pre-treatment of these animals with V.D3 caused further elevation of the values of these liver functional markers without altering kidney functional markers; continued weight loss; a lower lethal threshold dose of CCl4; and enhanced effects on lipid peroxidation and total antioxidant power. In contrast, exposure to V.D3 alone had no effect on plasma markers of liver or kidney damage or on total antioxidant power or lipid peroxidation. The potentiating effect of V.D3 was positively correlated with elevation of hepatic calcium levels. Furthermore, direct injection of CaCl2 also enhanced CCl4-induced hepatic injury. Since CaCl2 induced hypercalcemia transiently (within 3 h of injection), our results suggest that calcium enhances the CCl4-induced hepatotoxicity at an early stage via potentiation of oxidative stress.

English

Hibiscus is commonly used traditionally for the treatment of some diseases such as hypertension and as antidiabetic herbal medicine. The objective of the present study is to investigate the effect of the oral administration of aqueous methanolic extract of Hibiscus rosa-sinensis leaves (400 mg/Kg) on streptozotocin (STZ) induced diabetic rats and alteration in liver and kidney functions. The treatment of diabetic rats with hibiscus leaves extract reduced levels of plasma glucose, cholesterol, aspartate aminotransferase (AST), alanine aminotransferase (ALT), uric acid and creatinine and hepatic malondialdehyde that was elevated in diabetic rats. Moreover, the Hibiscus leaves extract mitigates the decrease in hepatic superoxide dismutase and plasma protein levels due to STZ injection. The treatment of rats with STZ only results in some pathological effects in liver and kidneys as degeneration in most of hepatocyte and glomeruli. The extract of H. rosa-sinensis leaves reduced the pathological changes. The treatment of diabetic rats with Hibiscus extract was shown to have hepatic and renal protective effects in diabetic rats induced experimentally. Here, two compounds, that is, orientin (Luteolin-8-C-glucoside) and verbascoside (phenylpropanoids glycoside) were isolated from H. rosa-sinsensis. The two compounds were identified by spectral analysis (UV, 1H and 13C-NMR). These results clearly indicate that aqueous leaves extract of H. rosa-sinensis possess antidiabetic and hypolipidemic effects in diabetic rats which may be due to antioxidant properties of the hibiscus extract. Key words: Hibiscus rosa-sinensis, hypoglycemic, antioxidant, orientin, verbascoside.

A New Oleanolic Acid Derivative against CCl₄-Induced Hepatic Fibrosis in Rats.

A novel hepatoprotective oleanolic acid derivative, 3-oxours-oleana-9(11), 12-dien-28-oic acid (Oxy-Di-OA), has been reported. In previous studies, we found that Oxy-Di-OA presented the anti-HBV (Hepatitis B Virus) activity (IC50 = 3.13 µg/mL). Remarkably, it is superior to lamivudine in the inhibition of the rebound of the viral replication rate. Furthermore, Oxy-Di-OA showed good performance of anti-HBV activity in vivo. Some studies showed that liver fibrosis may affiliate with HBV gene mutations. In addition, the anti-hepatic fibrosis activity of Oxy-Di-OA has not been studied. Therefore, we evaluated the protective effect of Oxy-Di-OA against carbon tetrachloride (CCl4)-induced liver injury in rats. Daily intraperitoneally administration of Oxy-Di-OA prevented the development of CCl4-induced liver fibrosis, which was evidenced by histological study and immunohistochemical analysis. The entire experimental protocol lasted nine weeks. Oxy-Di-OA significantly suppressed the increases of plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels (p < 0.05). Furthermore, Oxy-Di-OA could prevent expression of transforming growth factor β1 (TGF-β1). It is worth noting that the high-dose group Oxy-Di-OA is superior to bifendate in elevating hepatic function. Compared to the model group, Oxy-Di-OA in the high-dose group and low-dose group can significantly reduce the liver and spleen indices (p < 0.05). The acute toxicity test showed that LD50 and a 95% confidence interval (CIs) value of Oxy-Di-OA were 714.83 mg/kg and 639.73–798.73 mg/kg via intraperitoneal injection in mice, respectively. The LD50 value of Oxy-Di-OA exceeded 2000 mg/kg via gavage in mice. In addition, a simple and rapid high performance liquid chromatography-ultraviolet (HPLC-UV) method was developed and validated to study the pharmacokinetic characteristics of the compound. After single-dose oral administration, time to reach peak concentration of Oxy-Di-OA (Cmax = 8.18 ± 0.66 μg/mL) was 10 ± 2.19 h; the elimination half-life and area under the concentration-time curve from t = 0 to the last time of Oxy-Di-OA was 2.19 h and 90.21 μg·h/mL, respectively.