Effects of genotypes of hepatitis C virus on interferon treatment for chronic type C hepatitis

Interferon is commonly used for treatment of type C hepatitis, but the effects are variable and many factors may be responsible. Hepatitis C virus (HCV) can be classified into 4 types, PT, K1, K2a and K2b. Therefore, the responses to interferon treatment in patients with the different HCV genotypes were analyzed. Twenty-four patients with type C hepatitis were treated with 3 to 10 million units of various types of interferon for more than 8 weeks. HCV-RNA encoding the NS5 region (HCV-NS5) was positive in these 24 patients, 16 of which were classified with the K1 type and 8 with the K2 type of HCV. In all patients except for 2, HCV-NS5 became negative within 3 weeks of treatment without relation to the HCV genotypes. Serum alanine aminotransferase levels were normalized in 7 out of 8 patients in the K2 group and in 4 out of 16 patients in the K1 group at the end of 8 weeks. At the 24th week, ALT levels were normalized in 5 out of 6 patients in the K2 group, and in one out of 9 patients in the K1 group. The percentage of patients exhibiting a good response was significantly higher in the K2 group than in the K1 group at both observation periods. During the post-treatment periods, relapse following complete response was found in 3 patients in the K2 group and in one patient in the K1 group. The final effects of interferon were significantly better in the K2 group than in the K1 group.(ABSTRACT TRUNCATED AT 250 WORDS)

Dissociation of alpha 2-plasmin-inhibitor-plasmin complex and regeneration of plasmin activity by SDS treatment

In order to understand the mechanism for the complex between alpha 2-plasmin-inhibitor (alpha 2-PI) and plasmin to express its specific activity on fibrin autography after SDS-PAGE, we analyzed the effects of SDS on alpha 2-PI molecule and alpha 2-PI-plasmin complex. Treatment of alpha 2-PI by SDS at the concentrations of 0.01% and 0.1% abolished the activity of alpha 2-PI to form a stoichiometric complex with plasmin, whereas it did not interfere with plasmin's activity. More interestingly, in the case of 0.01% SDS, alpha 2-PI was further cleaved to a smaller molecule. Treatment of previously formed alpha 2-PI-plasmin complex by SDS at the concentrations of both 0.01% and 0.1% dissociated the complex and expressed specific amidolytic activity against tripeptide substrate (S-2251), which activity was totally quenched by aprotinin. When alpha 2-PI-plasmin complex was treated by higher concentration of SDS for 12 hours, dissociated free plasmin's band could be observed on SDS-PAGE analysis. It is likely, therefore, that the exposure of alpha 2-PI-plasmin complex to SDS during the procedure of SDS-PAGE dissociates the complex and expresses its specific proteolytic activity in fibrin autography. These features of alpha 2-PI and its complex with plasmin are similar to those of plasminogen activator inhibitor type 1 (PAI-1) and its complex with plasminogen activators (PAs), thus they may represent some common features of the SERPINS.

Serotonin as a factor involved in pathophysiology of thromboangiitis obliterans

Whole blood and plasma levels of serotonin (5-hydroxy-tryptamine, 5-HT) as well as its uptake and spontaneous release from blood platelets were studied in 20 patients suffering from thromboangiitis obliterans (TAO, Buerger's disease) and 20 healthy subjects matched in pairs for age. Results of patients suffering from thromboangiitis obliterans differed in several ways from those of controls. Whole blood 5-HT content was significantly lower in the group of patients compared to that of the control group. It was established that patients with Buerger's disease have significantly greater plasma concentrations of free serotonin. In Buerger's disease patients, maximal platelet serotonin uptake velocity (Vmax) was significantly decreased. It was associated with the enhanced spontaneous release of 5-HT from blood platelets. We conclude that impaired platelet serotonin uptake and increased local concentration of serotonin in the vicinity of platelets in Buerger's disease may lead to platelet activation via 5-HT2 receptors, and it could be involved in the pathogenesis of thromboembolic complications.

Differences in the hepatitis C virus genotypes in different countries

We recently classified the hepatitis C virus (HCV) into 4 types (HCV-PT, -K1, -K2a and -K2b) according to differences in nucleotide sequences. It was found that HCV-PT, the prototype reported from the U.S.A., was rare in Japan, suggesting that distribution of HCV genotypes may be different in various countries. The prevalence of HCV genotypes was therefore compared in different countries. Genotyping of HCV was performed by slot-blot hybridization analysis using cDNA probes specific to each type of HCV or by restriction fragment length polymorphism analysis. In 121 Japanese non-cancer patients, the prevalence of HCV genotypes was 77.7% for HCV-K1, 16.5% for HCV-K2a and 5.0% for HCV-K2b. HCV-PT was detected in only 1 patient (0.8%). The prevalence in 43 Japanese hepatocellular carcinoma (HCC) patients was 74.4% for HCV-K1, 18.6% for HCV-K2a and 4.7% for HCV-K2b. HCV-PT was found in only 1 sample. In 19 European non-cancer patients, HCV-PT was found in 42.1% and HCV-K1 was found in 52.6%. HCV-K2 was not found. All 7 samples from European HCC patients were HCV-K1, indicating a significantly higher prevalence than in non-cancer patients. In 13 Brazilian non-cancer patients, the distribution pattern was similar to that of the Europeans. In 10 samples from the U.S.A., HCV-PT was found in 70% and HCV-K2 was found in 1 sample. In 18 Chinese non-cancer patients, HCV-K1 was found in 44.4%, HCV-K2a in 50.0% and HCV-K2b in 5.6% HCV-PT was not found. Two samples from Chinese HCC patients were HCV-K1.(ABSTRACT TRUNCATED AT 250 WORDS)

Characteristic features of alcoholic liver disease in Japan: a review

The characteristics of alcoholic liver disease (ALD) in Japanese patients were reviewed and compared with those in Western countries. From the study in Japanese cases, it became clear that alcoholic fibrosis and chronic hepatitis induced by alcohol were types of ALD other than the traditional 3 types. Liver injury in Japanese cases was clearly milder than that in American cases. In American cases, the injury may be fully developed, because of greater alcohol and fat intake. This may be one reason why the two above types of ALD have not been mentioned in the literature of Western countries. In Japanese patients, hepatitis C virus (HCV) infection is not related to alcoholic fibrosis and alcoholic hepatitis. On the other hand, the prevalence of HCV markers was high in chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC) patients. Alcoholic hepatitis and chronic hepatitis are the high risk groups for the development of cirrhosis and the chronic hepatitis group is at high risk for the development of HCC. Although the risk is low in alcoholic fibrosis, some patients also develop cirrhosis. About half of the cases of cirrhosis may develop from alcoholic hepatitis and alcoholic fibrosis, and the remaining half cases may develop from chronic hepatitis. Over 80% of HCC cases may develop from chronic hepatitis in Japan. Chronic alcoholism enhanced the development of HCV-related HCC. Recent increase of HCC in alcoholic cirrhosis in Japan may be related to the increase of alcohol consumption, the increase of blood transfusions, and longer survival of cirrhosis patients.

Contribution of carbohydrate antigens sialyl Lewis A and sialyl Lewis X to adhesion of human cancer cells to vascular endothelium

The carbohydrate antigen, sialyl Lex, is known to be a ligand for the cell adhesion molecule called ELAM-1 (E-selectin, endothelial cell leukocyte adhesion molecule-1), which is present on cytokine-activated human endothelial cells. Recently, we reported that another carbohydrate antigen, sialyl Lea, can also serve as a ligand for ELAM-1 (A. Takada, K. Ohmori, N. Takahashi, K. Tsuyuoka, K. Yago, K. Zenita, A. Hasegawa, and R. Kannagi, Biochem. Biophys. Res. Commun., 179: 713-719, 1991). Both sialyl Lex and sialyl Lea are expressed in many human malignant cells. In order to assess the contribution of these carbohydrate antigens to the adhesion of human malignant cells to vascular endothelium, we selected a panel of 12 cultured human epithelial cancer cell lines and a panel of 12 human leukemia cell lines which express sialyl Lex and/or sialyl Lea antigens. All 12 epithelial cancer cell lines exhibited a clearly ELAM-1-dependent adhesion to cytokine-activated human umbilical vein endothelial cells, while only 3 of the 12 leukemia cell lines exhibited significant participation of ELAM-1 in the adhesion. With regard to epithelial cancer cells, the adhesion of 6 cancer cell lines, mostly of colon and pancreas origin, was dependent almost exclusively on sialyl Lea. A significant contribution of the sialyl Lex antigen was noted in the adhesion of the other 6 cell lines, including cancers of lung and liver origin. These results imply that the sialyl Lea/ELAM-1 adhesion system, as well as the sialyl Lex/ELAM-1 adhesion system, plays an important role in the adhesion of human cancer cells to human umbilical vein endothelial cells. With regard to leukemia cells, on the other hand, adhesion of the 3 leukemia cell lines that showed ELAM-1-dependent adhesion was mediated by the sialyl Lex antigen, and none of these leukemia cell lines expressed sialyl Lea or exhibited sialyl Lea-dependent adhesion.

Impaired fibrinolysis in hypertension and obesity due to high plasminogen activator inhibitor-1 level in plasma

In order to elucidate the influence of the risk factors of coronary heart disease on the fibrinolytic activity, relationships between blood pressure, body mass index (BMI), plasma lipoprotein (a) (Lp(a)) level and the plasma levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) were analyzed in the subjects with mild hypertension. Systolic blood pressure showed a positive correlation with total PAI-1 and free PAI-1. Diastolic blood pressure showed no correlation with these proteins involved in the fibrinolytic system. BMI had a positive correlation with total PAI-1, free PAI-1 and euglobulin clot lysis time (ECLT). Plasma Lp(a) level showed correlation with neither blood pressure nor fibrinolytic parameters, but it showed weak negative correlation with body mass index (BMI). These results suggest that high blood pressure and obesity tend to increase free PAI-1 which reduces fibrinolytic activity. Lp(a), however, seems not to influence directly the fibrinolytic system but may work to decrease fibrinolytic activity only in conjunction with other risk factors. The effects of daily drinking of alcohol and smoking on the fibrinolytic system were also investigated in the present study and we obtained the results that habitual drinking increased plasma levels of both tPA and PAI-1 whereas smoking did not affect fibrinolytic activity. These results suggest that risk factors for coronary heart disease such as hypertension and obesity are closely related to the impaired fibrinolysis.

The relationship between the development of alcoholic liver and pancreatic diseases and the induction of gamma glutamyl transferase

It is well known that the responses of serum gamma glutamyl transferase (GGT) to chronic alcohol drinking are different depending on the individual. In order to clarify the genetic backgrounds in the development of alcoholic liver and pancreatic diseases, the relationships between serum GGT response and alcoholic liver and pancreatic diseases in heavy drinkers were studied. The responses of GGT to alcohol drinking were classified into three groups: non-response, mild-response and hyperresponse. In alcoholic liver disease, non-responders were scarcely found and the response of GGT tended to increase in parallel with the progression of liver disease, when the hepatitis C virus (HCV) marker-positive patients were excluded. The differences in GGT levels between just after and at 4 weeks after abstinence in the HCV marker-negative patients were significantly higher than those in the HCV marker-positive patients. The rate of decrease in GGT activities during 4 weeks following abstinence was significantly higher in the HCV marker-negative patients than in the HCV marker-positive patients, indicating higher GGT induction in the HCV marker-positive patients. All patients with alcoholic pancreatitis, but without liver disease, were non-responders. All patients, except one, with severe pancreatitis were also non-responders. In alcoholic pancreatic disease, GGT induction correlated negatively with the development of pancreatitis. These results suggested that genetic polymorphism of GGT may link with the induction of GGT by alcohol drinking, and consequently link with the development of alcoholic liver and pancreatic diseases.

Correlation between serotonergic measures in cerebrospinal fluid and blood of subhuman primate

The relationship between the concentration of serotonin (5-hydroxytryptamine; 5-HT), its precursor; tryptophan (Trp) and the main metabolite 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF) and blood of monkey have been studied. 5-HT, Trp and 5-HIAA underwent circadian changes in both CSF and blood. Significant correlations were found between 5-HT, 5-HIAA and Trp in CSF and blood. The significance of these findings and their relationship to the use of peripheral serotonergic system as a functional model of the central nervous system are discussed.

Analysis of the characteristics of microheterogeneity of various serum glycoproteins in chronic alcoholics

It has been reported that microheterogeneity of serum glycoproteins including transferrin is found in alcoholic liver disease. In the present study, microheterogeneity of serum glycoproteins in alcoholic liver disease patients was analysed using the Western blotting technique after isoelectric focusing. Microheterogeneity was found for serum alpha 1-antitrypsin, alpha 2-macroglobulin, caeruloplasmin, alpha 1-acid glycoprotein and hemopexin as well as transferrin. Microheterogeneity disappeared following treatment with sialidase in some but not all glycoproteins. In hemopexin, microheterogeneity was recognized only after treatment with sialidase. These results suggest that mechanisms of microheterogeneity of serum glycoproteins in alcoholic liver disease may vary. One mechanism may be the interference of glycosylation of glycoproteins in the Golgi apparatus, and another may be the decrease of asialo-protein receptors in hepatocytes.

Studies on capillarization of the hepatic sinusoids in alcoholic liver disease

It has been reported that basement membranes were found around the sinusoidal walls in cirrhotic livers, indicating the development of capillarization of the sinusoids. It has been also emphasized that capillarization of the sinusoids is more prominent in alcoholic liver disease (ALD). In the present study, factor VIII related antigen (VIII-Ag) and UEA-1 were identified immunohistochemically in order to analyze capillarization of the sinusoids in chronic liver diseases. Electron microscopic studies on the endothelial cells and sinusoids were also performed. Electron microscopic studies revealed that the number of fenestra in the endothelial cells decreased and basement membranes were clearly observed in the space of Disse from an early stage of ALD. However, these changes were not observed in the early stage of non-ALD. VIII-Ag or UEA-1 was not stainable in the sinusoidal cells of normal livers or at an early stage of non-ALD. However, in ALD, both VIII-Ag and UEA-1 were clearly demonstrated in the sinusoidal cells from the early stage of fibrosis. These results suggest that the sinusoidal endothelial cells may transform to vascular endothelial cells from an early stage of ALD. The alterations in the sinusoidal endothelium and the basement membrane formation in the Disse space indicate that capillarization of the sinusoid may occur. Capillarization of the sinusoid may cause a disturbance in exchanges of many bioactive substances between the sinusoidal blood and hepatocytes across the Disse space and may thereby contribute to the pathogenesis of ALD.

Effects of alcohol on the replication of hepatitis C virus

We have reported that hepatitis C virus (HCV) RNA encoding the NS5 region (HCV-NS5) became negative following abstinence in some patients with alcoholic liver disease (ALD). In order to clarify the relationship between alcohol misuse (abuse) and the replication of HCV, serial changes of HCV-NS5 and the titer of HCV (HCV-titer) in blood after abstinence were studied in 11 male patients with ALD. Disappearance of HCV-NS5 after abstinence was found in five out of 11 patients (45%) and HCV-titer in blood decreased in all of these cases. In one patient, HCV-NS5 became positive and HCV-titers increased again following resumption of alcohol misuse. The etiology of liver disease in heavy drinkers was subdivided into three categories: alcohol alone, alcohol and HCV, and HCV alone, according to the diagnostic criteria of the Japanese research group for ALD. The etiology in four patients was a combination of alcohol and HCV, and was HCV alone in the remaining seven patients. In all four patients of the alcohol and HCV group, and one out of seven patients in the HCV alone group, HCV-NS5 became negative and HCV-titer decreased after abstinence. The decrease in HCV-titer was not related to the HCV genotypes. These results suggest that alcohol misuse may enhance the replication of HCV.

Relationship between alcoholic liver disease and HCV infection

The high prevalence of hepatitis C virus (HCV) markers in alcoholic liver cirrhosis (AL-LC) and hepatocellular carcinoma (HCC) suggests a close aetiopathogenic relationship between alcoholic liver disease (ALD) and HCV infection. In the present study, HCV markers in ALD were measured by the highly sensitive methods, and the changes of sequential HCV markers after abstinence in ALD patients were analysed in order to elucidate the effect of alcohol on HCV. Antibodies to HCV-related antigen were determined using the first or second generation test kit. HCV-RNA genomes encoding the NS-5 region were detected using the RT-PCR method. In the HCV-NS5 negative serum, HCV genomes of the 5'-noncoding region were detected using the two-stage PCR method. Titres of HCV-RNA were measured by multiple cyclic PCR and cDNA dot blotting. Typing of HCV genomes was carried out on the PCR product from the NS-5 region by slot blot hybridization using type-specific cDNA probes, or by restriction fragment length polymorphisms analysis. In alcoholic fibrosis and alcoholic hepatitis, the prevalence of HCV markers was low, suggesting that the main aetiological factor is alcohol but not HCV in these types of ALD. HCV markers were positive in the half of the patients with AL-LC, and in more than 80% of patients with AL-CH and AL-HCC, indicating that HCV infection closely relates to these types of ALD. The ratio of the K1 type to the K2 type of HCV genomes was 4:1 in all types of NANB liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Type IV collagen and laminin contents of livers from patients with alcoholic liver disease

Characteristic histological features of alcoholic liver disease (ALD) are pericellular and perivenular fibrosis. It has been emphasized from immunohistochemical studies that pericellular and perivenular fibrosis may be caused by the increase of type IV collagen (IV-C) and/or laminin (LM). However, quantitative changes of hepatic IV-C and LM contents in ALD are not well known. Recently, we have developed assay systems for IV-C and LM contents in liver biopsy specimens. In the present study, hepatic IV-C and LM contents in ALD and non-ALD patients were measured. Liver biopsy specimens were obtained from 36 patients with ALD, 24 patients with non-ALD and five patients without liver disease. IV-C and LM contents in liver biopsy specimens were measured using the one-step sandwich enzyme immunoassay system for human serum IV-C and LM levels. Total collagen (T-C) content was also measured by the method of Leon and Rojkind. Hepatic IV-C, LM and T-C contents were significantly higher in all types of liver disease than in controls, and tended to increase with the progression of fibrosis. Especially in ALD, both IV-C and LM contents increased from the early stage, and the values in each type of ALD were significantly higher than those in the corresponding type of non-ALD. The ratio of IV-C or LM to T-C was also significantly higher in ALD than in the corresponding non-ALD. The prominent increases of IV-C and LM at the early stage of fibrosis may be one of the characteristics of collagen metabolism in ALD.(ABSTRACT TRUNCATED AT 250 WORDS)

The alcohol-altered liver membrane antibody and hepatitis C virus infection in the progression of alcoholic liver disease

Progression of alcoholic liver disease is closely related to drinking habits. However, prognosis of alcoholic liver disease is not determined just by drinking habits, but also by other factors. In this study, the roles of alcohol-altered liver membrane antibody and hepatitis C virus infection were analyzed in alcoholic patients who were followed up for various lengths of time. Serial changes of liver histological appearance were analyzed in 39 patients with alcoholic liver disease who were followed for long periods (49.7 +/- 34.3 mo) and who underwent liver biopsy at least two times. Prognoses of 35 patients with alcoholic cirrhosis who were followed for more than 1 yr were also evaluated. Development of cirrhosis in alcoholic liver disease was significantly higher in the alcohol-altered liver membrane antibody-positive patients than in the patients negative for this antibody. On the other hand, hepatitis C virus markers were not related to development of cirrhosis. However, hepatocellular carcinoma developed more frequently in the hepatitis C virus marker-positive patients. In patients with cirrhosis, the cumulative rates of hepatocellular carcinoma development were significantly higher in the hepatitis C virus marker-positive patients than in the marker-negative patients. Cumulative survival rates in the hepatitis C virus marker-positive patients were significantly lower than rates in the hepatitis C virus marker-negative patients, even in noncancer patients. However, such differences were not observed in the alcohol-altered liver membrane antibody-positive and alcohol-altered liver membrane antibody-negative cirrhotic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of ethanol and acetaldehyde on the contraction of cultured Ito cells

The effects of ethanol (Et-OH) and acetaldehyde (Ac-CHO) on the contraction of cultured Ito cells were studied using a time-interval videotape recorder (VTR). Ito cells were isolated from Wistar rats and cultured for 4 days. The motion of the cells was recorded by VTR and the sequential changes of the surface area of the each cell were evaluated by an image analyzer. No contraction of Ito cells was observed after incubation with Et-OH (100 mM) or Ac-CHO (500 microM) alone. Ten nanomoles endothelin-1 (ET-1) caused Ito cells to contract gradually. Pre-incubation of ET-1 with Ac-CHO at 37 degrees C for 1 hr inhibited the contraction of Ito cells completely. This inhibition was not seen in pre-incubation of ET-1 with Et-OH. In addition, the Ito cells which were pre-cultured with Ac-CHO for 6 hr did not contract at all after incubation with ET-1. In the isoelectric focusing of ET-1, a band was clearly seen at pI 4.6 after the treatment with Et-OH as well as non-treated ET-1. Two extra bands of ET-1 appeared in the anodic side of the gel after treatment with Ac-CHO, indicating the conformational changes of ET-1. These results indicated that the contraction of Ito cells induced by ET-1 was inhibited completely by Ac-CHO. This inhibitory effect of Ac-CHO was thought to be caused by binding Ac-CHO to ET-1 itself or to ET-1 receptors.

Correlation between tumor proliferation and tumor tissue level of urokinase-type plasminogen activator

We established a xenotransplanted human colon cancer strain, TK-3, which produces urokinase-type plasminogen activator (U-PA) and carcinoembryonic antigen (CEA) simultaneously. Immunohistochemical staining of U-PA revealed that U-PA was located in the cytoplasm of cancer cells. Using TK-3, we investigated whether the tissue level of U-PA changed when the tumor proliferated locally. The mice were divided into three groups: mice of group A, B and C were sacrificed at 4, 5 and 6 weeks after tumor inoculation, respectively. The tissue level of U-PA was 0.78 +/- 0.183 ng/mg protein in group A, 0.95 +/- 0.189 in group B and 1.13 +/- 0.311 in group C. The values of groups B and C increased significantly compared with those of group A, and the tumor weight in each group showed a similar increase. The level of plasminogen activator inhibitor type 2 also increased (0.14 +/- 0.078 ng/mg protein in group A, 0.17 +/- 0.096 in group B, 0.24 +/- 0.172 in group C). On the other hand, the tissue level of CEA did not change significantly (78 micrograms/g tissue in group A, 88 in group B, 76 tissue in group C), and no correlation was observed between the tissue levels of U-PA and CEA. These results suggest that U-PA plays an important role not only in metastasis, but also in local tumor proliferation, and that its biological action in the autocrine system is independent of CEA.

Genetic factors related to the development of carcinoma in digestive organs in alcoholics

Heavy drinkers do not always develop alcoholic liver disease or cancer of the digestive organs, indicating that genetic factors may be involved. Recently, the presence of genetic polymorphisms of cytochrome P4502E1 (2E1) was confirmed. The genotype of 2E1 was separated into three types; type A which is homozygous for the c1 gene, type B which is heterozygous for the c1 and c2 genes, and type C which is homozygous for the c2 genes. In the present study the relationship between genotypes of 2E1 and digestive diseases, including alcoholic liver disease, was analyzed. In healthy controls, the prevalence of types A, B and C was 69%, 31% and 0%, respectively. In patients with esophageal cancer, four out of five patients (80%) were type B, and the prevalence of type B was significantly higher than that in normal controls. These results suggest that the c2 gene of 2E1 may be related to the development of esophageal cancer. In patients with gastric disease, the prevalence of types A and B was 72% and 28%, respectively. In patients with large bowel disease, the prevalence of type A was 83-100%, significantly higher than that in healthy controls. These results suggest that the c2 gene of 2E1 may not be related to the development of large bowel disease. However, the possibility should be considered that the c1 gene of 2E1 may link to its development. In this study, the relationship between the genotype of 2E1 and alcoholic liver disease was also analyzed. All patients with alcoholic liver disease, including one hepatoma, had the c2 gene but not the c1 gene. The frequency of the c2 gene was quite different from that in non-alcoholic liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of ethanol and acetaldehyde on the maturation of hepatic secretory glycoproteins

The effects of ethanol and acetaldehyde on the maturation and secretion of hepatic glycoproteins in cultured rat hepatocytes were analysed using a pulse-chase labelling method and autoradiography following two-dimensional gel electrophoresis. A spot for transferrin was detected at mol. wt 77,000 and pI 5.2-5.4 on the autoradiogram in the control culture. The spot for transferrin shifted to the more basic isoforms by treatment for 3 hr with monensin or tunicamycin. The spot for transferrin also shifted to the more basic side by treatment with acetaldehyde for 3 hr or by additional treatment for 3 hr following pretreatment with ethanol for 6 hr. However, the shift of transferrin was not observed following treatment with ethanol for 3 hr. These results suggest that glycosylation of secretory glycoproteins in the Golgi apparatus is inhibited by acetaldehyde, but not by ethanol itself, and that this inhibition may play an important role in the development of alcoholic liver disease.

Serotonergic measures in blood and brain and their correlations in rats treated with tranylcypromine, a monoamine oxidase inhibitor

Tranylcypromine, a monoamine oxidase inhibitor, was administered to male Wistar rats in order to investigate its effects on blood and brain serotonin related substances after 1, 4, and 24 h following injection and possible relations between serotonergic measures in central nervous system and periphery. The dose of the drug tested was responsible for an increase in blood serotonin with a simultaneous fall in its metabolite 5-hydroxyindoleacetic acid (5-HIAA) compared to either pretreatment or control values. These changes were the most marked after 4 and 24 h following tranylcypromine injection. Almost all brain areas studied (cerebellum, medulla, hypothalamus, striatum, midbrain, hippocampus, and cortex) were to be affected by monoamine oxidase inhibitor treatment. They exhibited a rise in serotonin content starting from 1 h after drug administration and lasted in many parts of the brain up to 24 h, which was accompanied by a parallel fall in 5-HIAA level. All these changes were significant when compared to baseline and control values. Alterations in blood serotonin correlated positively with changes in brain serotonin and negatively with brain 5-HIAA, while the opposite pattern of correlations was found regarding blood 5-HIAA and the content of serotonin and 5-HIAA in various brain areas studied. This pattern of correlations speaks in favor of an existence of mutual relations between blood and brain serotonin related substances. Our results suggest that blood serotonin and 5-HIAA may serve as an index of monoamine oxidase inhibitor action on the central serotonergic system.

Differentiation-dependent expression of sialyl stage-specific embryonic antigen-1 and I-antigens on human lymphoid cells and its implications for carbohydrate-mediated adhesion to vascular endothelium

Expression of two developmentally regulated carbohydrate antigens, the sialyl stage-specific embryonic antigen-1 (SSEA-1) and I-antigens, in human lymphocytes and lymphocytic leukemia cells was investigated using specific monoclonal antibodies. Sialyl SSEA-1 was expressed only on natural killer (NK) cells, and was essentially absent on resting mature T and B cells among normal peripheral lymphocytes. On the other hand, the I-antigen was strongly expressed on virtually all mature B cells, moderately expressed on most mature T cells, but not expressed on NK cells in normal donors. Expression of the two antigens on normal T and B cells was reversible; in vitro stimulation of normal lymphocytes with concanavalin A (Con A) resulted in the loss of I-antigen and appearance of sialyl SSEA-1 on CD3+ T blasts, whereas stimulation with pokeweed mitogen led to loss of I-antigen expression and appearance of sialyl SSEA-1 antigen on CD19+ B blasts. Among lymphocytic leukemia cells, sialyl SSEA-1 was detected primarily on leukemia cells having immature properties such as most common acute lymphocytic leukemia (cALL) blasts, while the I-antigen was frequently expressed on malignant cells having relatively mature properties, such as those found in adult T-cell leukemia or chronic lymphocytic leukemia, and only occasionally on cALL blasts. Among normal peripheral lymphocytes, the sialyl SSEA-1+I-antigen- NK cells selectively underwent E-selectin (ELAM-1, endothelial-leukocyte adhesion molecule-1)-dependent adhesion to endothelial cells, while the I-antigen+sialyl SSEA-1- mature T and B cells did not, in line with the recent finding that sialyl SSEA-1 serves as a specific ligand for E-selectin. Con A blasts, which are sialyl SSEA-1+I-antigen-, also exhibited significant E-selectin-dependent adhesion to endothelial cells. These results indicate that expression of the sialyl SSEA-1 and I-antigens varies alternately depending on the differentiation/activation status of the lymphocytes, and that this at least partly regulates the behavior of lymphocytes at the vessel wall.

Ethanol and acetaldehyde metabolism in cultured rat hepatocytes

In the present study, ethanol (Et-OH) and acetaldehyde (Ac-CHO) metabolism in primary cultured hepatocytes isolated from chronically alcohol-fed rats were analysed to elucidate the characteristics of the metabolism of Ac-CHO produced through the non-alcohol dehydrogenase (non-ADH) pathway. Dimethyl sulfoxide was added to the culture medium to prevent a decrease in P450 IIE1 activity. Ac-CHO formed in the culture medium was trapped by semicarbazide to prevent a reutilization of Ac-CHO by hepatocytes. The degradation rate of Ac-CHO in the liver was similar in alcohol and non-alcohol-treated rats. Therefore, the characteristic of the metabolism of Ac-CHO in the chronically alcohol-fed rats was not clarified in this study. The possibility that the Ac-CHO trapping by semicarbazide was only 70%, and that the remaining Ac-CHO was reutilized for oxidation in the hepatocytes, should be considered. Some method to trap Ac-CHO completely in the culture medium is needed to clarify the characteristics of Ac-CHO metabolism.