Raman imaging of rat nonalcoholic fatty liver tissues reveals distinct biomolecular states

An essential challenge in diagnosing states of nonalcoholic fatty liver disease (NAFLD) is the early prediction of progression from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH) before the disease progresses. Histological diagnoses of NAFLD rely on the appearance of anomalous tissue morphologies, and it is difficult to segment the biomolecular environment of the tissue through a conventional histopathological approach. Here, we show that hyperspectral Raman imaging provides diagnostic information on NAFLD in rats, as spectral changes among disease states can be detected before histological characteristics emerge. Our results demonstrate that Raman imaging of NAFLD can be a useful tool for histopathologists, offering biomolecular distinctions among tissue states that cannot be observed through standard histopathological means.

Diagnostic accuracy of non-invasive tests for advanced fibrosis in patients with NAFLD: an individual patient data meta-analysis

OBJECTIVE

Liver biopsy is still needed for fibrosis staging in many patients with non-alcoholic fatty liver disease. The aims of this study were to evaluate the individual diagnostic performance of liver stiffness measurement by vibration controlled transient elastography (LSM-VCTE), Fibrosis-4 Index (FIB-4) and NAFLD (non-alcoholic fatty liver disease) Fibrosis Score (NFS) and to derive diagnostic strategies that could reduce the need for liver biopsies.

DESIGN

Individual patient data meta-analysis of studies evaluating LSM-VCTE against liver histology was conducted. FIB-4 and NFS were computed where possible. Sensitivity, specificity and area under the receiver operating curve (AUROC) were calculated. Biomarkers were assessed individually and in sequential combinations.

RESULTS

Data were included from 37 primary studies (n=5735; 45% women; median age: 54 years; median body mass index: 30 kg/m²; 33% had type 2 diabetes; 30% had advanced fibrosis). AUROCs of individual LSM-VCTE, FIB-4 and NFS for advanced fibrosis were 0.85, 0.76 and 0.73. Sequential combination of FIB-4 cut-offs (<1.3; ≥2.67) followed by LSM-VCTE cut-offs (<8.0; ≥10.0 kPa) to rule-in or rule-out advanced fibrosis had sensitivity and specificity (95% CI) of 66% (63-68) and 86% (84-87) with 33% needing a biopsy to establish a final diagnosis. FIB-4 cut-offs (<1.3; ≥3.48) followed by LSM cut-offs (<8.0; ≥20.0 kPa) to rule out advanced fibrosis or rule in cirrhosis had a sensitivity of 38% (37-39) and specificity of 90% (89-91) with 19% needing biopsy.

CONCLUSION

Sequential combinations of markers with a lower cut-off to rule-out advanced fibrosis and a higher cut-off to rule-in cirrhosis can reduce the need for liver biopsies.

Label-free Assessment of the Nascent State of Rat Non-alcoholic Fatty Liver Disease Using Spontaneous Raman Microscopy

Spontaneous Raman microscopy, which can detect molecular vibrations in cells and tissues, could be a useful tool for the label-free assessment of non-alcoholic fatty liver disease (NAFLD). However, it is unclear whether it can be used to evaluate the nascent state of NAFLD. To address this, we analyzed the Raman spectra of rat liver tissues in the nascent state of NAFLD upon excitation at 532 nm. Raman and histochemical analyses were performed of liver tissues from rats fed a high-fat, high-cholesterol diet (HFHCD). Raman microscopic imaging analysis of formalin-fixed thin tissue slices showed hepatic steatosis, as revealed by the Raman band at 2,854 cm⁻¹, whereas lipid droplets were not detectable by hematoxylin-eosin staining of images until 3 days after feeding a HFHCD. Raman signals of retinol at 1,588 cm⁻¹ emitted from hepatic stellate cells were distributed alongside hepatic cords; the retinol content rapidly decreased after feeding a HFHCD, whereas hepatic lipid content increased inversely. Raman microscopic analysis of the surface of fresh ex vivolivers enabled early detection of lipid accumulation after a 1-day feeding a HFHCD. In conclusion, spontaneous Raman microscopy can be applied to the label-free evaluation of the nascent state of NAFLD liver tissues.

Early Tumor Shrinkage as a Predictive Factor for Outcomes in Hepatocellular Carcinoma Patients Treated with Lenvatinib: A Multicenter Analysis

We investigated the association between early tumor shrinkage (ETS) and treatment outcome in patients with hepatocellular carcinoma treated with lenvatinib (LEN). A retrospective analysis was performed in 104 patients. ETS was defined as tumor shrinkage at the first evaluation in the sum of target lesions’ longest diameters from baseline according to the Response Evaluation Criteria in Solid Tumors (RECIST). The median overall survival (OS) was not reached, whereas the median progression-free survival (PFS) was 5.0 months. The receiver operating characteristic curve analysis in differentiating long-term responders (PFS ≥ 5.0 months) from short-term responders (PFS < 5.0 months) revealed an ETS cut-off value of 10%. ETS ≥ 10% was significantly correlated with better PFS and OS compared with ETS < 10%. Additionally, ETS ≥ 10% showed a better discrimination ability on prognosis compared with modified RECIST-based objective response at the first evaluation. Multivariate analysis confirmed ETS ≥ 10% as an independent predictor of better OS, as well as a Child–Pugh score of 5 and macrovascular invasion. In conclusion, ETS ≥ 10% was strongly associated with outcome in patients treated with LEN. This biomarker could allow earlier assessment of the treatment response and guide treatment decision-making for HCC.

Impact of Relative Dose Intensity of Early-phase Lenvatinib Treatment on Therapeutic Response in Hepatocellular Carcinoma

BACKGROUND

Factors associated with response to lenvatinib have not been clarified in patients with hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

This study retrospectively analyzed 50 patients treated with lenvatinib as first-line therapy between March 2018 and March 2019. Patients were divided into two groups by the Modified Response Evaluation Criteria in Solid Tumours (mRECIST) (responders and non-responders, whose best overall responses were complete (CR)/partial response (PR) and stable (SD)/progressive disease (PD), respectively). Factors associated with response were assessed, including the relative dose intensity 8 weeks after lenvatinib induction (8W-RDI).

RESULTS

The best overall responses were 0/22/14/14 of CR/PR/SD/PD. Multivariate analysis revealed that only 8W-RDI was significantly associated with response. The receiver operating characteristic curve for 8W-RDI in differentiating responders from non-responders revealed a cut-off value of 75%. Patients with 8W-RDI ≥75% experienced a higher response rate and longer progression-free survival than patients with 8W-RDI <75%.

CONCLUSION

Our results suggest that maintaining an RDI ≥75% during the initial 8 weeks of lenvatinib treatment has a favorable impact on response.

Raman spectroscopic histology using machine learning for nonalcoholic fatty liver disease

Histopathology requires the expertise of specialists to diagnose morphological features of cells and tissues. Raman imaging can provide additional biochemical information to benefit histological disease diagnosis. Using a dietary model of nonalcoholic fatty liver disease in rats, we combine Raman imaging with machine learning and information theory to evaluate cellular-level information in liver tissue samples. After increasing signal-to-noise ratio in the Raman images through superpixel segmentation, we extract biochemically distinct regions within liver tissues, allowing for quantification of characteristic biochemical components such as vitamin A and lipids. Armed with microscopic information about the biochemical composition of the liver tissues, we group tissues having similar composition, providing a descriptor enabling inference of tissue states, contributing valuable information to histological inspection.

Insulin resistance increases the risk of incident type 2 diabetes mellitus in patients with non-alcoholic fatty liver disease

AIM

Type 2 diabetes mellitus (T2DM) is a major complication of patients with non-alcoholic fatty liver disease (NAFLD). The aim of this retrospective study is to determine the risk factors for development of T2DM in patients with biopsy-proven NAFLD.

METHODS

One hundred and sixty two consecutive patients with biopsy-proven NAFLD who received a 75-g oral glucose tolerance test were enrolled as the total cohort. Among them, we analyzed 89 patients without T2DM diagnosed by oral glucose tolerance test to estimate the cumulative rate for development of T2DM as the follow-up cohort.

RESULTS

Of 162 patients, the glucose tolerance pattern were DM in 45 patients (27.8%), impaired glucose tolerance in 68 (42.0%), and normal glucose tolerance in 49 (30.2%). Patients with NAFL tended to be more likely to have normal glucose tolerance than those with non-alcoholic steatohepatitis (NASH). The serum levels of pre- and post-load insulin were significantly higher in the NASH group. Of 89 patients without T2DM, 13 patients newly developed T2DM during a follow-up period of 5.2 years. The cumulative rate of T2DM incidence was 8.8% at the end of the 5th year and 23.4% at the end of the 10th year. Multivariate analysis identified homeostasis model of assessment - insulin resistance (≥3.85, hazard ratio 40.1, P = 0.033) as an independent risk factor for development of T2DM.

CONCLUSIONS

Patients with NASH have an underlying potential of glucose intolerance. In NAFLD patients, insulin resistance is the most important risk factor for the incidence of T2DM. Appropriate therapy against insulin resistance could be needed for patients with NAFLD to prevent development of T2DM.

Hepatic nucleotide binding oligomerization domain-like receptors pyrin domain-containing 3 inflammasomes are associated with the histologic severity of non-alcoholic fatty liver disease

AIM

To examine the role of nucleotide binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasomes in the development of non-alcoholic fatty liver disease (NAFLD).

METHODS

Levels of mRNAs encoding NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, procaspase-1, interleukin (IL)-1β, and IL-18 were quantified by real-time polymerase chain reaction in 91 liver samples and 37 blood samples from biopsy-proven patients with NAFLD. Adiponutrin (also called PNPLA3) polymorphisms (rs738409, C > G) were determined in 74 samples by genotyping assays. Serum IL-1β and IL-18 levels were measured by enzyme-linked immunosorbent assay and liver tissue caspase-1 expression by immunostaining.

RESULTS

Hepatic NLRP3, procaspase-1, IL-1β, and IL-18 mRNA levels were significantly higher in NAFLD patients than in controls and were significantly associated with adiponutrin G alleles. Blood procaspase-1 mRNA was significantly higher in NAFLD patients than in healthy controls. Hepatic procaspase-1 and IL-1β mRNA levels correlated significantly with lobular inflammation, hepatocyte ballooning, and NAFLD activity score. Serum IL-18 levels were significantly higher in NAFLD patients than in controls, while IL-1β levels were non-significantly higher. Serum IL-1β and IL-18 concentrations correlated significantly with steatosis, NAFLD activity score, and transaminase levels. Serum IL-1β levels were significantly associated with adiponutrin G alleles. Scattered caspase-1-positive cells were present in portal tracts and inflammatory foci and around ballooning hepatocytes. Immunofluorescence staining showed that caspase-1 colocalized with the macrophage marker CD68.

CONCLUSIONS

The NLRP3 inflammasomes are primed in the liver, influenced by adiponutrin genotypes, and activated in Kupffer cells and/or macrophages in NAFLD, leading to histological progression through IL-1β and IL-18 production.

Development of hepatocellular carcinoma in Japanese patients with biopsy-proven non-alcoholic fatty liver disease: Association between PNPLA3 genotype and hepatocarcinogenesis/fibrosis progression

AIM

Some patients with non-alcoholic fatty liver disease (NAFLD) develop hepatocellular carcinoma (HCC). Patatin-like phospholipase domain containing 3 (PNPLA3) rs738409 (encoding the I148M variant) has been associated with advanced fibrosis and HCC. We determined the risk factors for HCC, including the PNPLA3 rs738409 polymorphism, in Japanese patients with biopsy-proven NAFLD.

METHODS

In this retrospective cohort study, we analyzed hepatocarcinogenesis in 238 patients. PNPLA3 rs738409 genotype was determined by allelic discrimination in 130 patients. Among them, 86 patients who were followed up for >5 years and without liver cirrhosis were analyzed to clarify the relationship between PNPLA3 genotype and long-term changes in biomarkers.

RESULTS

Of 238 patients, PNPLA3 genotype frequencies were: CC, 0.14; CG, 0.46; and GG, 0.40. During a follow-up period of 6.1 years, 10 patients (4.2%) with non-alcoholic steatohepatitis developed HCC. The cumulative rate of HCC was 1.9% at the end of the 5th year and 8.3% at the end of the 10th year. Multivariate analysis identified PNPLA3 genotype GG (hazard ratio, 6.36; P = 0.019) and fibrosis stage (fibrosis stage 3/4; hazard ratio, 24.4; P = 0.011) as predictors of HCC development. In the long follow-up cohort, a larger reduction in platelet count was found in the GG group (P = 0.032) despite a larger reduction in alanine aminotransferase (P = 0.023) compared to that in the CC/CG group.

CONCLUSIONS

In Japanese patients with NAFLD, severe fibrosis and PNPLA3 GG genotype were predictors of HCC development, independent of other known risk factors. Patients with the PNPLA3 GG genotype have the potential for a decreased platelet count, even when alanine aminotransferase levels are well controlled.

Effect of 12-week dulaglutide therapy in Japanese patients with biopsy-proven non-alcoholic fatty liver disease and type 2 diabetes mellitus

AIMS

No pharmacological therapies have been established for non-alcoholic fatty liver disease (NAFLD) with type 2 diabetes mellitus (T2DM). The aim of this retrospective study is to evaluate the efficacy and safety of dulaglutide, a novel glucagon-like peptidase-1 receptor agonist, in Japanese NAFLD patients with T2DM.

METHODS

Fifteen biopsy-proven NAFLD patients with T2DM refractory to diet intervention who received once weekly dulaglutide 0.75 mg for 12 weeks were retrospectively enrolled after exclusion of two patients by 12 weeks. In five patients, transient elastography and body composition were also evaluated before and after the treatment.

RESULTS

Not only body weight and hemoglobin A1c but also transaminase activities were significantly decreased after the 12-week therapy with dulaglutide. Total body fat mass and liver stiffness measurement also decreased after the treatment.

CONCLUSION

Dulaglutide, a new glucagon-like peptidase-1 receptor agonist, could be a novel promising agent for the treatment for NAFLD patients with T2DM due to its efficacy in body weight reduction, the nature of weekly injection, and patient preference. Prospective randomized controlled trials are warranted to confirm this impact of dulaglutide on NAFLD with T2DM.

Effect of sodium glucose cotransporter 2 inhibitor on liver function tests in Japanese patients with non-alcoholic fatty liver disease and type 2 diabetes mellitus

AIM

No pharmacological therapies have been established for non-alcoholic fatty liver disease (NAFLD). Sodium glucose cotransporter 2 inhibitor (SGLT2I) was developed for the treatment of adults with type 2 diabetes mellitus (T2DM). The aim of this retrospective study is to evaluate the efficacy of SGLT2I in NAFLD patients with T2DM.

METHODS

Twenty-four biopsy-proven NAFLD patients with T2DM who received SGLT2I for 24 weeks were retrospectively enrolled as the SGLT2I group. Another 21 NAFLD patients with T2DM treated with dipeptidyl peptidase-4 inhibitor (DPP4I) for 24 weeks were selected as the DPP4I group. Clinical data were evaluated at baseline and at 4, 12, and 24 weeks. Seventeen patients in the SGLT2I group were evaluated by body composition before and after therapy.

RESULTS

Not only body weight and hemoglobin A1c but also transaminase activities were significantly decreased in the SGLT2I group. Reductions in transaminase activities were similar between SGLT2I and DPP4I groups. In the SGLT2I group, body mass index and fasting plasma glucose also decreased after the treatment.

CONCLUSION

Sodium glucose cotransporter 2 inhibitor can be a novel promising agent for the treatment for NAFLD patients with T2DM. Prospective randomized controlled trials are warranted to confirm this efficacy of SGLT2I on NAFLD with T2DM.

Liver stiffness measurement to platelet ratio index predicts the stage of liver fibrosis in non-alcoholic fatty liver disease

AIM

Platelet count and liver stiffness measurement (LSM) using transient elastography could identify significant fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). We constructed a novel index combining LSM with platelet count for staging fibrosis in Japanese patients with NAFLD.

METHODS

We recruited 173 Japanese patients with liver biopsy-proven NAFLD. The areas under the receiver operating characteristic curves were calculated and compared with established parameters and scoring systems for staging liver fibrosis.

RESULTS

After excluding 10 patients in whom LSM failed, 163 patients with NAFLD were enrolled. The areas under the receiver operating characteristic curves of the LSM/platelet ratio (LPR) index for detecting fibrosis ≥stage 1, ≥stage 2, and ≥stage 3 were the greatest (0.835, 0.913, and 0.936, respectively) compared with those for various other parameters and established scoring systems, such as LSM, type IV collagen 7 s domain, platelet count, NAFIC score, fibrosis-4 index, NAFLD fibrosis score, aspartate aminotransferase/alanine aminotransferase ratio, and aspartate aminotransferase to platelet ratio index. The optimal cut-off, positive predictive, and negative predictive values of the LPR index for detecting ≥stage 3 fibrosis were 0.60, 48.9%, and 99.2%, whereas those of LSM were 10.0 kPa, 35.0%, and 99.0%, respectively. The novel LPR index helps avoid biopsies in a larger percentage of patients with NAFLD compared with that LSM alone.

CONCLUSIONS

The LPR index was the best predictor for staging fibrosis in patients with NAFLD. It represents a simple and non-invasive alternative to liver biopsy in clinical practice.

Association of coronary artery calcification with liver fibrosis in Japanese patients with non-alcoholic fatty liver disease

AIMS

Cardiovascular events are the leading cause of death among patients with non-alcoholic fatty liver disease (NAFLD), but their relationship remains unclear. This study examined the association between coronary atherosclerosis and liver fibrosis, represented by the coronary artery calcification (CAC) score and non-invasive fibrosis markers, respectively.

METHODS

Among 698 patients with chest pain or electrocardiographic abnormalities who underwent coronary computed tomography (CT) between April 2006 and March 2010, those with known liver disorders or history of emergency coronary angioplasty were excluded, leaving 366 patients for this study. Diagnosis of NAFLD was based on abdominal CT and history of alcohol consumption. Subjects with CAC of 100 AU or more were categorized into the high-risk group for cardiovascular events. Patient records were examined for clinical parameters including CAC score and non-invasive fibrosis marker FIB-4 index.

RESULTS

Ninety-four patients (25.7%) had NAFLD. In this group, univariate analysis identified old age, high diastolic blood pressure, high liver to spleen ratio and high FIB-4 index as risk factors for cardiovascular events and multivariate analysis identified age of 66 years or older and FIB-4 index of 2.09 or more as the significant risk factors. For the observation period until August 2014, the cumulative proportion of PCI performance was significantly higher in patients with FIB-4 of 2.09 or more than those with FIB-4 of less than 2.09.

CONCLUSION

The progression of arteriosclerosis and that of liver fibrosis may be associated in NAFLD patients. The FIB-4 index can be easily determined and thus can be a useful marker for predicting cardiovascular events in NAFLD patients.

Serum alanine aminotransferase predicts the histological course of non-alcoholic steatohepatitis in Japanese patients

AIM

Some cases with non-alcoholic fatty liver disease (NAFLD), particularly non-alcoholic steatohepatitis (NASH), can ultimately progress to liver cirrhosis. However, studies to clarify factors predictive of histological change in patients with NASH remain scarce. Our aim is to determine predictors of histological progression in Japanese patients with biopsy-proven NASH.

METHODS

This retrospective cohort study enrolled 52 patients with NASH who underwent serial liver biopsies. Histological evaluation included NAFLD activity score (NAS) and liver fibrosis. The median interval between initial and second liver biopsies was 968 days. An alanine aminotransferase (ALT) response was defined as a decrease of 30% or more from baseline.

RESULTS

Of 52 patients, NAS was ameliorated in 30.8%, deteriorated in 30.8% and remained unchanged in 38.4%. Liver fibrosis was improved in 25.0% of patients, progressed in 25.0% and remained stable in 50.0%. Multivariate analysis identified ALT non-response as a predictor of deterioration of NAS (hazard ratio [HR], 5.85; P = 0.031) and progression of liver fibrosis (HR, 4.50; P = 0.029). The mean annual rate of fibrosis was 0.002 stages/year overall, increasing to 0.15 stages/year in ALT non-responders.

CONCLUSION

A lack of reduction in serum ALT level by at least 30% from baseline was a predictor for histological progression in patients with NASH. Serum ALT level is a better predictor of histological change than insulin resistance or bodyweight and can be a valid index in treatment. Serum ALT should be strictly controlled to prevent liver histological progression in patients with NASH.

Drug-induced liver injury in a chronic hepatitis C patient treated by peginterferon, ribavirin and simeprevir

A 56-year-old male patient with chronic hepatitis C was treated with pegylated interferon (PEG IFN)-α-2b and ribavirin (RBV) for 72 weeks in 2006. The patient achieved an early virological response (EVR); however, hepatitis C relapsed 12 weeks after discontinuation of PEG IFN and RBV. In 2012, the patient was treated with a PEG IFN/RBV/telaprevir combination therapy. After 5 days of treatment, he suffered from a telaprevir-associated skin rash on his body and four limbs. He chose to be treated with PEG IFN and RBV until 60 weeks. He again achieved EVR but no sustained virological response. In 2014, he was treated with PEG IFN/RBV/simeprevir combination therapy. He achieved rapid virological response, but after 6 weeks of therapy, a striking elevation of serum aminotransferase level was recorded with no accompanying skin rash; he was admitted to our hospital. PEG IFN/RBV/simeprevir was stopped, but sodium valproate (400 mg/day), which had been administrated for more than 10 years to prevent epilepsy was continued. Liver biopsy revealed typical features of drug-induced liver injury. After stopping PEG IFN/RBV/simeprevir, serum aminotransferase levels soon returned to the normal range. We diagnosed this case to be simeprevir-induced hepatitis clinically and histologically. Physicians need to stay alert to the possibility of drug-induced liver injury in using simeprevir.

Lower levels of insulin-like growth factor-1 standard deviation score are associated with histological severity of non-alcoholic fatty liver disease

AIM

Growth hormone (GH) deficiency may be associated with histological progression of non-alcoholic fatty liver disease (NAFLD) which includes non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH). Insulin-like growth factor 1 (IGF-1) is mainly produced by hepatocytes and its secretion is stimulated by GH. Our aim was to determine whether more histologically advanced NAFLD is associated with low circulating levels of IGF-1 in Japanese patients.

METHODS

Serum samples were obtained in 199 Japanese patients with biopsy-proven NAFLD and in 2911 sex- and age-matched healthy people undergoing health checkups. The serum levels of IGF-1 were measured using a commercially available immunoradiometric assay. The standard deviation scores (SDS) of IGF-1 according to age and sex were also calculated in NAFLD patients.

RESULTS

The serum IGF-1 levels in NAFLD patients were significantly lower (median, 112 ng/mL) compared with the control population (median, 121 ng/mL, P < 0.0001). IGF-1 SDS less than -2.0 SD from median were found in 11.6% of 199 patients. NASH patients exhibited significantly lower levels of IGF-1 SDS (n = 130; median, -0.7) compared with NAFL patients (n = 69; median, -0.3; P = 0.026). The IGF-1 SDS values decreased significantly with increasing lobular inflammation (P < 0.001) and fibrosis (P < 0.001). In multiple regressions, the association between the IGF-1 SDS values and the severity of NAFLD persisted after adjusting for age, sex and insulin resistance.

CONCLUSION

Low levels of circulating IGF-1 may have a role in the development of advanced NAFLD, independent of insulin resistance. Supplementation with GH/IGF-1 may be a candidate for the treatment of NASH.

Predictors of malignancies and overall mortality in Japanese patients with biopsy-proven non-alcoholic fatty liver disease

AIM

Some patients with non-alcoholic fatty liver disease (NAFLD) develop hepatocellular carcinoma (HCC) and have higher mortality than others. The evidence causally linking NAFLD to extrahepatic malignancies is scarce. Our aim was to determine the incidence of and risk factors for HCC, extrahepatic cancer and mortality in Japanese patients with biopsy-proven NAFLD.

METHODS

This retrospective cohort study analyzed outcomes including onset of malignant tumors and death in 312 patients with NAFLD diagnosed by liver biopsy.

RESULTS

Of 312 patients, 176 (56.4%) were diagnosed with non-alcoholic steatohepatitis. During a median follow-up period of 4.8 years (range, 0.3-15.8), six patients (1.9%) developed HCC, and 20 (6.4%) developed extrahepatic cancer. Multivariate analysis identified fibrosis stage (≥3; hazard ratio [HR], 12.3; 95% confidence interval [CI], 1.11-136.0; P = 0.041) as a predictor for HCC and type IV collagen 7s (>5 ng/mL; HR, 1.74; 95% CI, 1.08-2.79; P = 0.022) as a predictor for extrahepatic cancer. Eight patients (2.6%) died during the follow-up period. The most common cause of death was extrahepatic malignancy. None died of cardiovascular disease. Multivariate analysis identified type IV collagen 7s (>5 ng/mL; HR, 3.38; 95% CI, 1.17-9.76; P = 0.024) as a predictor for mortality.

CONCLUSION

The incidence of extrahepatic cancer was higher than that of HCC. Severe fibrosis was a predictor for HCC. Patients with NAFLD and elevated type IV collagen 7s levels are at increased risk for extrahepatic cancer and overall mortality.

Blockade of interleukin 6 signalling ameliorates systemic insulin resistance through upregulation of glucose uptake in skeletal muscle and improves hepatic steatosis in high-fat diet fed mice

BACKGROUND & AIMS

Mice fed high-fat diet (HFD) demonstrate obesity-related systemic insulin resistance (IR). Aim of this study is to clarify the role of interleukin (IL)-6 in IR in vivo focusing on skeletal muscle, adipose tissue and liver.

METHODS

Plasma markers of IR and hepatic IL-6 signalling were examined in eight-week HFD feeding C57/BL6 mice. Furthermore, IR-related molecules in skeletal muscles, adipose tissues and livers were investigated following a single injection of anti- IL-6 receptor neutralizing antibody (MR16-1) in two-week HFD feeding mice. To investigate the role of IL-6 in hepatic steatosis by prolonged HFD, hepatic triglyceride accumulation was assessed in eight-week HFD feeding mice with continuous MR16-1 treatment.

RESULTS

High-fat diet for both 2 and 8 weeks elevated plasma IL-6, insulin and leptin, which were decreased by MR16-1 treatment. A single injection of MR16-1 ameliorated IR as assessed by glucose and insulin tolerance test, which may be attributable to upregulation of glucose transporter type 4 via phosphorylation of AMP-activated protein kinase as well as upregulation of peroxisome proliferator-activated receptor alpha in livers and, particularly, in skeletal muscles. MR16-1 also decreased mRNA expression of leptin and tumour necrosis factor-alpha and increased that of adiponectin in adipose tissue. High-fat diet for 8 weeks, not 2 weeks, induced hepatic steatosis and increased hepatic triglyceride content, all of which were ameliorated by MR16-1 treatment.

CONCLUSIONS

Blockade of excessive IL-6 stimulus ameliorated HFD-induced IR in a skeletal muscle and modulated the production of adipokines from an early stage of NAFLD, leading to prevention of liver steatosis for a long term.

Impact of Helicobacter pylori eradication on circulating adiponectin in humans

BACKGROUND

The relationship between Helicobacter pylori infection and metabolic syndrome is not well understood. Adiponectin is an adipose-derived protein considered to play a significant role in the development of metabolic syndrome. The aim of this study was to clarify the influence of H. pylori infection on circulating adiponectin in humans.

METHODS

In a prospective study, 456 patients underwent endoscopy and H. pylori testing. All of the 338 H. pylori -positive patients received eradication therapy. Treatment was successful in 241 patients. Circulating adiponectin and other metabolic parameters were measured at baseline in all patients and 12 weeks after eradication therapy in those initially positive for H. pylori.

RESULTS

Circulating adiponectin levels were not different between H. pylori -positive and H. pylori -negative patients. In the group with successful eradication, levels of total adiponectin and each multimer form were significantly increased after therapy. Conversely, the levels of total adiponectin and high-molecular-weight adiponectin, but not middle-molecular-weight and low-molecular-weight adiponectin, were increased in the group with unsuccessful eradication after the therapy.

CONCLUSIONS

Eradication therapy of H. pylori increased circulating adiponectin levels in Japanese individuals and could be beneficial for preventing metabolic syndrome conditions.

[A case of hypervascular hyperplastic nodule in chronic alcoholic liver disease with corona-like enhancement in the late phase image of CT during hepatic arteriography]

A 46-year-old woman was admitted to our hospital with hepatic encephalopathy due to alcoholic liver disease. A hepatic nodule (20 mm in diameter) in S7 was enhanced in the early phase of contrast CT. No significant findings were observed in the late phase of contrast CT and SPIO MRI. The late phase of CT during hepatic arteriography showed corona-like enhancement of the nodule. The nodule was diagnosed as a hypervascular hyperplastic nodule, based on histological examinations and immunohistochemical results with antibodies against CD68 and CD34.

The analysis of the functions of human B and T cells in humanized NOD/shi-scid/gammac(null) (NOG) mice (hu-HSC NOG mice)

'Humanized mice' are anticipated to be a valuable tool for studying the human immune system, but the reconstituted human immune cells have not yet been well characterized. Here, we extensively investigated the differentiation and functions of human B and T cells in a supra-immunodeficient mouse strain, NOD/shi-scid/gammac(null) (NOG) reconstituted with CD34(+) hematopoietic stem cells obtained from umbilical cord blood. In these hu-HSC NOG mice, the development of human B cells was partially blocked, and a significant number of B-cell progenitors accumulated in the spleen. The mature CD19(+)IgM(+)IgD(+) human B cells of the hu-HSC NOG mice could produce IgG in vivo and in vitro by antigenic stimulation. In contrast, although human T cells with an apparently normal phenotype developed, most of them could neither proliferate nor produce IL-2 in response to antigenic stimulation by anti-CD3 and anti-CD28 antibodies in vitro. The positive selection of human T cells in the thymus was sufficiently functional, if not complete, and mainly mediated by mouse class II, suggesting that the human T cells lost their function in the periphery. We found that multiple mechanisms were involved in the T-cell abnormalities. Collectively, our results demonstrate that further improvements are necessary before humanized mice with a functional human immune system are achieved.

Stimulative effect of cadmium on prostaglandin E2 production in primary mouse osteoblastic cells

We have reported that cadmium (Cd) stimulates bone resorption via prostaglandin E2 (PGE2), which is mainly produced in osteoblasts. Prostaglandin (PGs) is regulated by arachidonic acid (AA) release by phospholipase A2 (PLA2) and its conversion to PGs by cyclooxygenase (COX). In the present study, we investigated the possibility that Cd-induced PGE2 synthesis was mediated through PLA2 or COX or both using primary mouse osteoblastic cells in serum-free medium. Cd at 1 microM and above stimulated 14C-AA release from 14C-AA-prelabeled osteoblastic cells. PLA2 activity of cytosolic fraction in Cd-treated cells preferentially hydrolyzed AA at the Sn2 position of phospholipids and was inhibited by arachidonyltrifluoromethyl ketone (AACOCF3), an inhibitor of cytosolic PLA2 (cPLA2). Cd at 1 microM and above increased cPLA2 activity and the level of constitutive cPLA2 mRNA. Secretory PLA2 mRNA was not detected. On the other hand, Cd at 1 microM and above stimulated PGE2 production and its production was inhibited by an inhibitor of COX-2 (NS-398). Cd at 1 microM and above markedly stimulated COX-2 mRNA expression and slightly increased the level of COX-1 mRNA. An inhibitor of COX-1 (varelylsalicylic acid) did not affect Cd-induced PGE2 production. In addition, Cd-induced PGE2 synthesis was inhibited by AA-COCF3, On the other hand, IL-1 alpha, an inducer of COX-2, did not stimulated PGE2 production in present culture system. When IL-1 alpha- or Cd-treated cells were incubated with AA for 10 minutes, IL-1 alpha-treated cells as well as Cd-treated ones caused an increase in PGE2 production. This suggests that the mechanism of Cd-induced PGE2 production is different from that of IL-1 alpha, which may require an activation of cPLA2. From these results, it was found that Cd by itself stimulated PGE2 production by two successive steps that Cd increased cPLA2 activity and then COX-2 induction.

Induction of metallothionein isoforms in rat hepatoma cells by various anticancer drugs

The induction of metallothionein (MT) isoforms (MT-1, -2) by anticancer drugs was investigated in cultured rat hepatoma H4 II E C3 cells. The steady-state expression of MT-1 mRNAs was higher than that of MT-2 mRNAs. During incubation of the cells with various anticancer drugs, namely, adriamycin, epirubicin, cis-diamminedichloroplatinum(II) (CDDP), and cis-diammine(1, 1-cyclobutyldicarboxylato)platinum(II), both MT-1 and MT-2 mRNAs were coordinately inducible: the levels of isoMT mRNA reached a maxim of approximate by 6-fold at 3 h. Immunofluorescent studies revealed that the cytosolic fluorescence in the cells exposed to 1 microM CDDP for 48 h was more intensified than that in the untreated cells. Transfer of antisense oligonucleotides resulted in marked reduction of isoMT mRNA, and upon exposure to 5 microM CDDP for 48 h, the viabilities of these cells dropped to 25.8% of the controls. These results indicate that anticancer drugs are potent inducers of MT isoforms in hepatoma cells and that a decrease in cellular MTs enhances the susceptibility of hepatoma cells to CDDP. Thus, we conclude that endogenous MTs play a role in determining the sensitivity or resistance of cancer cells to clinically important anticancer agents.

Differential expression of transforming growth factor-beta and its receptors in hepatocytes and nonparenchymal cells of rat liver after CCl4 administration

BACKGROUND/AIMS

Transforming growth factor-beta (TGF-beta) is a family of multifunctional proteins that regulate hepatocyte proliferation, and biosynthesis of the extracellular matrix. In this study we examined whether modulation of TGF-beta receptor expression contributes to the liver diseases.

METHODS

The mRNA expression of TGF-beta1, TGF-beta type I receptor (TGFbetaRI), TGF-beta type II receptor (TGFbetaRII) and TGF-beta type III receptor (TGFbetaRIII) in rat livers injured by CCl4 administration was studied by Northern blotting. The mRNA expression patterns were confirmed by in situ hybridization.

RESULT

The peak of TGF-beta1 mRNA expression was observed 48 h after acute intoxication with CCl4 in nonparenchymal cells. However, the levels of TGFbetaRI and TGFbetaRII mRNA expression decreased from 24 h to 48 h and from 12 h to 48 h, respectively, and returned to the normal level by 72 h. TGFbetaRII mRNA expression was depressed more and for longer than that of TGFbetaRI mRNA. Analysis in separated hepatocytes and nonparenchymal cells from the injured livers indicated that the mRNA changes occurred in hepatocytes. Nonparenchymal cells expressed TGFbetaRI and TGFbetaRII mRNAs at constant levels during liver regeneration. TGFbetaRIII mRNA, which also decreased after 12 h, was not apparent in hepatocytes but only in nonparenchymal cells.

CONCLUSIONS

These observations suggest that: (i) whenever TGF-beta1 is increased in CCl4-treated livers, it may induce liver fibrogenesis via nonparenchymal cells; (ii) the mitoinhibitory effect of TGF-beta1 on hepatocytes is transiently relieved by down-regulation of TGF-beta receptors for 72 h post-damage; and (iii) the resistance to TGF-beta growth inhibition between 24 to 48 h may be predominantly due to down-regulation of the expression of TGFbetaRII.

Induction of hepatocyte growth factor activator messenger RNA in the liver following tissue injury and acute inflammation

Hepatocyte growth factor activator (HGFA) is a serine protease that is responsible for localized activation of hepatocyte growth factor (HGF) in injured tissue. The activated HGF may be involved in regeneration of the injured tissue. HGFA is produced and secreted by the liver and circulates in the plasma as an inactive zymogen. In response to tissue injury, the HGFA zymogen is converted to the active form by limited proteolysis. In this study, we isolated a rat HGFA complementary DNA (cDNA) clone and analyzed the production of HGFA messenger RNA (mRNA) in response to tissue injury using this cDNA clone as a probe. The nucleotide sequence of the cDNA revealed that the amino acid sequences of rat and human HGFA showed a high degree of conservation in the regions of the characteristic domain structures, suggesting that rat and human HGFA are activated by a similar mechanism and have similar enzymatic activities in vivo. Tissue distribution analysis showed that the liver was the major site of rat HGFA mRNA synthesis. Moreover, the cells producing HGFA mRNA were identified as parenchymal liver cells. The level of HGFA mRNA increased in the liver after hepatotoxin or nephrotoxin treatment. This increase was also observed during acute inflammation induced by turpentine. These results suggest that the increase in production of HGFA mRNA in response to tissue injury is the result of an inflammatory response, and that HGFA is an acute phase protein.

Induction of the human gene for p44, a hepatitis-C-associated microtubular aggregate protein, by interferon-alpha/beta

A hepatitis-C-associated microtubular aggregate protein, referred to as p44, has been identified as a cytoplasmic antigen in the hepatocytes of chimpanzees infected with hepatitis C virus. The production of p44 mRNA is markedly induced in the liver of chimpanzees infected with hepatitis C or hepatitis D virus. To examine the mechanism of this induction, we isolated a genomic clone for the human p44 protein and analyzed its structure. The human p44 gene spans approximately 14 kbp of DNA and consists of nine exons separated by eight introns. An interferon-stimulated response element, which confers inducibility by interferon-alpha/beta, was found in the promoter region of the gene. Northern-blot analysis revealed that the human p44 gene is inducible by interferon-alpha/beta, but not by interferon-gamma. Functional analysis demonstrated that the interferon-stimulated response element in the promoter region of the gene mediates the inducibility of the gene by interferon-alpha/beta. Thus, the human p44 gene is a member of the family of interferon-alpha/beta inducible genes. The protein p44 may be one of the mediators involved in the antiviral action of interferon.

Characterization of the promoter region of the rat hepatocyte-growth-factor/scatter-factor gene

Hepatocyte growth factor/scatter factor (HGF/SF) is a potent mitogen for hepatocytes in primary culture. In response to liver damage, the levels of HGF/SF mRNA change in various tissues. In this study, we isolated a genomic DNA fragment containing the promoter region of the rat HGF/SF gene and analyzed transcription-initiation sites and their utilization in response to acute liver injury. Rat HGF/SF-mRNA synthesis starts from at least three sites in the liver, spleen and kidney. One of these sites is preferentially utilized in the liver and spleen in response to acute liver injury. In the 5' flanking region, several cytokine-related sequence elements that might be involved in the regulation of HGF/SF-gene expression are located near the transcription-initiation sites. The effects of cytokines related to these sequence elements on the production of HGF/SF mRNA were examined using a cell culture system. Transforming growth factor-beta 1 (TGF-beta 1) inhibits the production of HGF/SF mRNA by Shay granulocytic sarcoma-derived cells. The TGF-beta 1-inhibitory element, one of the sequence elements present in the promoter sequence, may mediate the inhibition of HGF/SF-gene expression by TGF-beta 1.

Primary structure of rat hepatocyte growth factor and induction of its mRNA during liver regeneration following hepatic injury

Overlapping cDNA clones for rat hepatocyte growth factor (rHGF) were isolated by cross-hybridization with the cloned cDNA for human hepatocyte growth factor (hHGF) and the nucleotide sequence of the cDNA was determined. The entire primary structure of rHGF was deduced from the sequence. Comparison of the amino acid sequences between rat and human HGFs revealed that the two sequences are highly conserved throughout the protein structures, suggesting that rat and human HGFs may be functionally similar. Responses of the rHGF mRNA during liver regeneration in rats were examined by Northern blot hybridization analysis with the aid of the cDNA probe for rHGF. The mRNA levels increased in the liver and spleen but not in the kidney after administration of carbon tetrachloride. At the maximum level of induction, the rHGF mRNA increased in the liver about 4.5-fold over its normal level. The mRNA levels also increased in the liver and spleen after administration of D-galactosamine. On the other hand, no obvious increase of the mRNA was observed in the liver and spleen after partial hepatectomy. These observations suggest that HGF may function as a regulator of liver regeneration following hepatic injury caused by hepatotoxins.

[Factor V inhibitor with double cancer]

A 84-year-old man was admitted with palpitation, edema of legs and anemia during a long course of diabetes mellitus, prostatic hypertrophy and prostatic cancer. He revealed purpura on the hands and massive microhematuria. He had received antibiotic therapy for a urinary tract infection for a period of time, but he had no history of hemorrhagic tendency or blood transfusion. Coagulation studies showed the prolongation of whole blood clotting time and PT (prothrombin time). Activity of factor V was 14% of that normal control plasma. The titer of factor V inhibitor was 4.9 Bethesda units/ml. The inhibitor of the patient was supposed to belong to IgA and IgG judging from inhibitor neutralization test. PT was improved after discontinuance of administration of antibiotics and administration of azathioprine. Moreover, even after administration of prednisolone with antibiotics, PT and activity of factor V recovered to normal range. He died from respiratory failure. Autopsy revealed double cancer of prostate and descending colon. The appearance of factor V inhibitor was likely caused by antibiotics, double cancer, and age-related immune disorders.

Statocyst-Induced Eye Movements in the Crab Scylla Serrata

1. Irrigation of the statocysts of the crab Scylla serrata will activate the oculomotor neurones associated with eye movements.

2. An investigation of the central mechanism of statocyst-induced nystagmus has been started with the description of the statocyst canals and a characterization of the sensory input from the hair receptors in the canals.

3. The canals are shaped like two toroids joined at approximately right angles to one another. Direct observation of isolated statoliths and glass models of them shows that when they are rotated, fluid moves around the circumference of the statocyst canals and displaces the hair receptors protruding into them. The direction of displacement of the different groups of receptors in both statocysts is related to the axes of rotation and provides a unique output for rotation about each axis.

4. Electrical recordings from the three types of receptor hairs show that the thread hairs are most probably the receptors responsible for detection of rotation about the vertical axis. The free hook hairs are sensitive enough to detect rotation about the horizontal axes. The statolith hairs are sensitive to maintained changes of position.