A novel treatment for refractory primary biliary cirrhosis?

BACKGROUND/AIMS

Bezafibrate is naturally used for hyperlipidemia worldwide. In 1992 Day et al reported that the value of ALP and gamma-GTP in hyperlipidemia declined after administering bezafibrate orally. We conducted a study to investigate whether or not ALP and gamma-GTP in primary biliary cirrhosis which is characterized by the elevation of these enzymes improved after taking bezafibrate.

METHODOLOGY

We administered bezafibrate additionally for 6 months to 13 patients with primary biliary cirrhosis (refractory PBC) whose liver enzymes (ALP or gamma-GTP) did not remain within normal range out of 21 patients treated by monotherapy of ursodeoxycholic acid for 18 months.

RESULTS

At 2, 4, and 6 months, gamma-GTP level significantly decreased compared with that prior to the initiation of bezafibrate. At 4 and 6 months, ALP level significantly decreased compared with that prior to the initiation. At 2, 4 and 6 months, ALT level significantly decreased compared with that prior to the initiation. The value of IgG and IgM was also reduced significantly 6 months after the initiation.

CONCLUSIONS

If the effectiveness of bezafibrate for primary biliary cirrhosis is confirmed histologically and by a randomized trial, a combination therapy of bezafibrate and ursodeoxycholic acid appear to be the medical treatment of choice for primary biliary cirrhosis in the future.

Testing of SHIRPA, a mouse phenotypic assessment protocol, on Dmd(mdx) and Dmd(mdx3cv) dystrophin-deficient mice

The SHIRPA protocol was proposed as a rapid, comprehensive screening method for qualitatively abnormal phenotypes in the mouse (Rogers et al., Mamm Genome 8, 711, 1997). This screening technique is currently being used to identify mutants induced by N-ethylnitrosourea (ENU) mutagenesis (Brown and Nolan, Hum Mol Genet 7, 1627, 1998). SHIRPA can be used to identify mutants with neuromuscular abnormalities, but the sensitivity of the protocol is unknown. We tested two dystrophin-deficient mutants Dmd(mdx) and Dmd(mdx3cv), both of which are indistinguishable from wild-type by a simple visual assessment, at different ages, using the primary screen of the SHIRPA protocol. The most dramatic observation was that both Dmd(mdx) and Dmd(mdx3cv) mice showed extreme fatigue after testing, while mice from the same C57BL strains appeared unaffected. Each strain of dystrophin-deficient mice showed a different profile in locomotor activity and deficiencies in the wire maneuver, righting reflex, and negative geotaxis tests. Furthermore, the wire maneuver test indicated an earlier onset of muscular impairment in Dmd(mdx) than Dmd(mdx3cv) mice. These data suggest that the SHIRPA primary screen is effective not only in identifying subtle neuromuscular mutants, but also in distinguishing qualitative differences between mutants with neuromuscular abnormalities.

A juvenile case of overlap syndrome of systemic lupus erythematosus and polymyositis, later accompanied by systemic sclerosis with the development of anti-Scl 70 and anti-Ku antibodies

We describe a 16-year-old girl with an overlap syndrome consisting of systemic lupus erythematosus (SLE) from the age of 7 and polymyositis (PM) from the age of 10, later accompanied by systemic sclerosis (SSc) from the age of 15. She was diagnosed as having SLE with exudative malar erythema, photosensitivity, and discoid rashes with positive antinuclear antibody (ANA) and anti-DNA antibody titers. The diagnosis of PM was also made in accordance with findings of a high titer of muscle enzymes and a muscle biopsy specimen demonstrating marked degeneration of the muscle fibers and perivascular infiltration of mononuclear cells. She developed Raynaud's phenomenon and pitting ulcers on her fingers with positive anti-Scl 70 and anti-Ku antibodies, leading to a diagnosis of SSc. The patient was treated with prednisolone. To our knowledge this is the youngest case of SLE-PM overlap syndrome later accompanied by SSc.

Targeted delivery of anticancer drugs with intravenously administered magnetic liposomes in osteosarcoma-bearing hamsters

Although active targeting of anticancer drugs using magnetically responsive carriers is a very attractive treatment approach for solid tumors, successful results are limited. In particular, the therapeutic utility of intravenously administered magnetically responsive carriers has to date not been clearly established. The present study investigates magnetic liposomes designed to act as anticancer drug carriers, which can be effectively delivered to solid tumors via intravenous administration. Magnetic liposomes with incorporated adriamycin (magnetic ADR liposomes) were prepared by the reverse-phase evaporation method, and an in vivo study was carried out to assess the magnetic targeting of these liposomes to hamster osteosarcoma. The average diameter of liposomes thus prepared was 146 nm. Syrian male hamsters inoculated with osteosarcoma, Os515, in the right hind limb were studied 7 days after inoculation. After the hamsters had received an intravenous administration of either magnetic ADR liposomes or ADR solution (corresponding to 5 mg ADR/kg), the ADR concentrations in plasma, tumor, liver, lung, heart, and kidney were determined at designated time intervals. Administration of magnetic ADR liposomes under magnetic force using a permanent magnet (0.4 tesla) implanted in solid tumor produced an approximately 4-fold higher maximum ADR concentration in the tumor than did administration of ADR solution. The former administration modality induced an increase in ADR concentration in the liver and lung and a decrease in the heart compared with concentrations produced by the latter. The present results indicated that intravenously administered magnetic ADR liposomes can be used to effectively deliver ADR to osteosarcoma implanted with a magnet, as well as to the lung, a common site of metastases for osteosarcoma. Our results also suggest that this new treatment approach, which involves a combination of magnet implantation at the target site and intravenous administration of magnetic liposomes, can improve the clinical chemotherapy of solid tumors.

Adeno-associated virus vector transduction of vascular smooth muscle cells in vivo

Adeno-associated virus (AAV) vectors might offer solutions for restenosis and angiogenesis by transducing nondividing cells and providing long-term gene expression. We investigated the feasibility of vascular cell transduction by AAV vectors in an in vivo rabbit carotid artery model. Time course of gene expression, inflammatory reaction to the vector, and effects of varying viral titer, exposure time, and intraluminal pressures on gene expression were examined. Recombinant AAV vectors with an Rous sarcoma virus promoter and alkaline phosphatase reporter gene were injected intraluminally into transiently isolated carotid segments. Following transduction, gene expression increased significantly over 14 days and then remained stable to 28 days, the last time point examined. Medial vascular smooth muscle cells were the main cell type transduced even with an intact endothelial layer. Increasing the viral titer and intraluminal pressure both enhanced transduction efficiency to achieve a mean of 34 +/- 7% of the subintimal layer of smooth muscle cells expressing gene product. A mild inflammatory reaction, composed of T cells with only rare macrophages, with minimal intimal thickening was demonstrated in 40% of transduced vessels; inflammatory cells were not detected in sham-operated control arteries. These findings demonstrate that AAV is a promising vector for intravascular applications in coronary and peripheral vascular diseases.

Gene gun-mediated delivery of an interleukin-12 expression plasmid protects against infections with the intracellular protozoan parasites Leishmania major and Trypanosoma cruzi in mice

An interleukin-12 (IL-12) expression plasmid was transferred, using a gene gun, to mice infected with Leishmania major or Trypanosoma cruzi. Transfer of the IL-12 gene to susceptible BALB/c mice resulted in regression of lesion size and reduced the number of parasites in draining lymph nodes (LN) at the site of L. major infection. Coincident with these protective effects, the T-helper type (Th) response shifted towards Th1, as evaluated by cytokine production in vitro and L. major-specific antibody responses. Protective effects of the IL-12 gene were also observed in T. cruzi infection. Treatment of BALB/c mice infected with T. cruzi enhanced the production of interferon-gamma (IFN-gamma) by spleen cells, while suppressed production of interleukin-10 (IL-10) compared with control mice. Administration of anti-CD4 or anti-CD8 monoclonal antibody (mAb) abolished the protective immunity against T. cruzi infection, and treatment with the IL-12 gene could not restore the resistance in these mice. Mice depleted of natural killer (NK) cells with anti-asialo GM1 also became susceptible to infection, while the resistance was restored when these mice were treated with the IL-12 gene. Thus, target cells for the treatment appear to be CD4+ and CD8+ T cells, which are ordinarily activated by NK cells. These results suggest that the transfer of cytokine genes using a gene gun is an effective method for investigating the roles of cytokines and gene therapy in infectious diseases.

A crack model of the Hiroshima atomic bomb: explanation of the contradiction of "Dosimetry system 1986"

There has been a large discrepancy between the Dosimetry system 1986 (DS86) and measured data, some of which data in Hiroshima at about 1.5 km ground distance from the hypocenter are about 10 times larger than the calculation. Therefore its causes have long been discussed, since it will change the estimated radiation risks obtained based on the Hiroshima and Nagasaki data. In this study the contradiction was explained by a bare-fission-neutron leakage model through a crack formed at the time of neutron emission. According to the present calculation, the crack has a 3 cm parallel spacing, which is symmetric with respect to the polar axis from the hypocenter to the epicenter of the atomic bomb. We made also an asymmetric opening closing 3/4 of this symmetric geometry, because there are some data which shows asymmetry. In addition, the height of the neutron emission point was elevated 90 m. By using the asymmetric calculation, especially for long distant data located more than 1 km, it was verified that all of the activity data induced by thermal and fast neutrons, were simultaneously explained within the data scattering. The neutron kerma at a typical 1.5 km ground distance increases 3 and 8 times more than DS86 based on the symmetric and asymmetric model, respectively.

Circulating levels of soluble CD30 and other markers in colorectal cancer patients

In a search for new biologic serum tumor markers with prognostic value we evaluated the soluble form of the CD30 (sCD30), a marker of cells producing T helper 2 (Th2)-type cytokines, interleukin-1 receptor antagonist (IL-1ra), soluble interleukin-2 receptor (sIL-2R), soluble tumor necrosis factor -type I, -type II (sTNF-R55, -75) and immunosuppressive acidic protein (IAP) in patients, with advanced colorectal cancer. The data showed that abnormal levels of sCD30 were detected in eight (80.0%) out of ten patients. In contrast, sCD30 levels were not detected in healthy volunteers. The relationship between sCD30, sIL-2R and IAP were positively correlated. In contrast, sCD30 and IL-1ra were negatively correlated. These results suggested that IL-1ra may play a role, at least in part, to inhibit CD30 release, and sCD30 appears to be a new biologic serum tumor marker of possible use in the clinical setting of cancer patients.

Crystal structure of beta-amylase from Bacillus cereus var. mycoides at 2.2 A resolution

The crystal structure of beta-amylase from Bacillus cereus var. mycoides was determined by the multiple isomorphous replacement method. The structure was refined to a final R-factor of 0.186 for 102,807 independent reflections with F/sigma(F) > or = 2.0 at 2.2 A resolution with root-mean-square deviations from ideality in bond lengths, and bond angles of 0.014 A and 3.00 degrees, respectively. The asymmetric unit comprises four molecules exhibiting a dimer-of-dimers structure. The enzyme, however, acts as a monomer in solution. The beta-amylase molecule folds into three domains; the first one is the N-terminal catalytic domain with a (beta/alpha)8 barrel, the second one is the excursion part from the first one, and the third one is the C-terminal domain with two almost anti-parallel beta-sheets. The active site cleft, including two putative catalytic residues (Glu172 and Glu367), is located on the carboxyl side of the central beta-sheet in the (beta/alpha)8 barrel, as in most amylases. The active site structure of the enzyme resembles that of soybean beta-amylase with slight differences. One calcium ion is bound per molecule far from the active site. The C-terminal domain has a fold similar to the raw starch binding domains of cyclodextrin glycosyltransferase and glucoamylase.

DNA immunization with Plasmodium falciparum serine repeat antigen: regulation of humoral immune response by coinoculation of cytokine expression plasmid

We immunized mice with plasmid expressing the 47-kDa amino-terminal domain of the Plasmodium falciparum serine repeat antigen (SERA) using gene gun and investigated humoral immune response to SERA antigen. Significant SERA-specific IgG was observed in BALB/c mice after immunization three times with SERA expression plasmid. Furthermore, these levels were increased by the coinoculation of cytokine (IFN-gamma, IL-4, GM-CSF, or IL-12) expression plasmid. In respect to the SERA-specific Ig subclasses, coinoculation of IFN-gamma, GM-CSF, or IL-12 expression plasmid increased the levels of SERA-specific IgG2a, and these were much higher than that in mice immunized with SERA expression plasmid alone. In contrast to the SERA-specific IgG2a, coinoculation of any cytokine expression plasmid did not change the levels of SERA-specific IgG1. These results indicate that cytokine expression plasmid enhances and regulates humoral immune response elicited by SERA DNA immunization.

Mobilization of primitive haemopoietic progenitor cells and stem cells with long-term repopulating ability into peripheral blood in mice by pegylated recombinant human megakaryocyte growth and development factor

We investigated in detail the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on peripheral blood progenitor cell (PBPC) mobilization in male BDF1 mice. Treatment with PEG-rHuMGDF for 5 d stimulated a striking expansion of the circulating levels of multiple types of colony-forming units in culture (CFU-c), including CFU-granulocyte-macrophage, CFU-megakaryocyte, burst-forming units-erythroid, and multipotent CFU-c, and primitive day-12 CFU-spleen. All of these progenitors were mobilized into the peripheral blood (PB) with similar kinetics; their numbers peaked after the cessation of treatment and then declined earlier than platelet numbers peaked. The maximal increase in any of the four CFU-c in the PB was attained with at least 300 microg/kg/d of PEG-rHuMGDF, whereas peripheral platelet counts plateaued at 30 microg/kg/d. Adoptive transfer with PB from PEG-rHuMGDF-treated donor mice resulted in greater survival of lethally irradiated recipients. The majority of the recipients that survived at 187 d after transplantation with PEG-rHuMGDF-mobilized PB showed significant donor engraftment at the progenitor cell level. The combined administration of appropriate doses of PEG-rHuMGDF and recombinant human granulocyte colony-stimulating factor induced a synergistic increase in the circulating levels of the four CFU-c compared to either factor alone. These results indicate that PEG-rHuMGDF as a single agent can mobilize a full spectrum of PBPCs in mice.

Estimation of dose absorbed fraction for 131I-beta rays in rat thyroid

The dose absorbed fraction of rat thyroid by internal deposit of 131I has been calculated as a function of effective diameter of thyroid. The calculations were done using two types of Monte Carlo simulations: one was by a simple energy-loss calculation in spherical volume according to the electron stopping power, and another by a more realistic simulation using Monte Carlo N-Particle Transport code system Version 4A (MCNP). These two calculations were consistent with each other within a deviation of 5%. The absorbed fractions in spherical thyroid were drastically changed up to 5 mm diameter, and then almost all energy was deposited within 10 mm diameter. For the practical application to the animal experiment, the absorbed fractions of ellipsoid-shaped thyroids were also calculated for 1-, 4- and 9-week-old rats, where the fractions were estimated to be 0.61, 0.67 and 0.68, respectively. It was also found that the absorbed fraction of the ellipsoid with various dimensions can be simulated by a calculation for spherical volume with a comparable effective diameter.

Systemic delivery of interleukin 10 by intramuscular injection of expression plasmid DNA prevents autoimmune diabetes in nonobese diabetic mice

We previously demonstrated that intramuscular plasmid injection serves as a useful method of long-term systemic delivery of cytokines. In the present study, we assess intramuscular DNA injection as a means of systemically delivering interleukin 10 (IL-10), a cytokine with immunosuppressive properties, and preventing the progression of autoimmune diabetes in the nonobese diabetic (NOD) mouse, an excellent model for human insulin-dependent diabetes mellitus (IDDM). We injected IL-10 expression plasmid (pCAGGS-IL10) or a control pCAGGS plasmid into the muscles of NOD mice twice at 3 and 5 weeks of age. IL-10 was detectable by ELISA in the sera of mice injected with pCAGGS-IL10 for more than 2 weeks after the injection. Although the severity of insulitis at 13 weeks of age was not improved by the intramuscular injection of pCAGGS-IL10, the incidence of diabetes was markedly reduced in NOD mice injected with pCAGGS-IL10 as compared with those injected with pCAGGS or as compared with nontreated NOD mice. These results show that the progression of autoimmune diseases in mice can effectively be suppressed by intramuscular DNA injection, and suggest that this method is potentially applicable to the treatment of human autoimmune diseases.

Translocation of platelets into Disse spaces and their entry into hepatocytes in response to lipopolysaccharides, interleukin-1 and tumour necrosis factor: the role of Kupffer cells

BACKGROUND/AIMS

Injection into mice of a small dose of either a lipopolysaccharide or interleukin-1 induces a slowly developing accumulation of 5-hydroxytryptamine, predominantly in the liver. We have established that this 5-hydroxytryptamine accumulation is the result of the translocation of platelets to hepatic sinusoidal spaces and, further, into Disse spaces, and that the platelets make direct contact with hepatocytes. In the present study, we report our recent findings on this phenomenon.

METHODS

Platelets contain a large amount of 5-hydroxytryptamine, but the 5-hydroxytryptamine content of the liver is normally very small. Therefore, the translocation of platelets to the liver was assessed by measuring 5-hydroxytryptamine as in previous studies, and it was also analysed by electron microscopy.

RESULTS

Anti-platelet agents, such as heparin and inhibitors of prostaglandin synthesis, were ineffective in preventing the lipopolysaccharide-induced accumulation of 5-hydroxytryptamine in the liver. Of the various cytokines tested, only interleukin-1 and tumour necrosis factor induced such an accumulation of 5-hydroxytryptamine. Intravenous injection of liposomes encapsulating dichloromethylene bisphosphonate resulted in an almost complete depletion of macrophages from the liver. The lipopolysaccharide- and cytokine-induced hepatic accumulations of 5-hydroxytryptamine were abolished almost completely in such macrophage-depleted mice. Electron microscopy revealed no accumulation of platelets in the liver after injection of lipopolysaccharide into the macrophage-depleted mice. Surprisingly, in normal mice injected with lipopolysaccharide, several platelets were found inside some hepatocytes, even though there was no visible damage to these hepatocytes. In fact, there were many polysomes around the degranulated platelets within the hepatocytes, suggesting an enhanced protein synthesis.

CONCLUSION

These results suggest that, in response to lipopolysaccharide, interleukin-1 or tumour necrosis factor, platelets translocate into the liver in a way that is different from aggregation, and that some, at least, enter hepatocytes. During these processes, hepatic macrophages play an essential role.

Displacement of platelets from blood to spleen following intravenous injection of liposomes encapsulating dichloromethylene bisphosphonate

Liposomes encapsulating dichloromethylene bisphosphonate (Cl2MBP-liposomes) have been shown to cause selective depletion of phagocytic macrophages. We have shown that intravenous injection of Cl2MBP-liposomes into mice induces an almost complete depletion of F4/80-positive cells (mature macrophages) in the liver and in the splenic red pulp, but not in the lung. Platelets in the mouse contain a large amount of 5-hydroxytryptamine (5HT; serotonin) and so, by measuring 5HT, it is possible to assess the translocation of platelets to tissues. The injection of Cl2MBP-liposomes was found to induce a prolonged and marked increase in 5HT that occurred selectively in the spleen. On the other hand, 5HT in the blood decreased by as much as 50%. These changes in 5HT corresponded well with each other in terms of both time course and dose-response relationship. To judge from measurements made at the peak of the response, the 5HT increase in the spleen corresponded to about 80% of the 5HT lost from the blood. Electron microscopic analysis revealed a great accumulation of platelets in the splenic cords. We have shown that aggregation and degranulation of platelets in the lung is involved in rapid anaphylactoid shock induced within 10 min of intravenous injection into mice of a lipopolysaccharide [Shibazaki, M., Nakamura, M., Endo, Y., 1996. Biphasic, organ-specific, and strain-specific accumulation of platelets induced in mice by a lipopolysaccharide from Escherichia coli and its possible involvement in shock. Infect. Immun. 64, 5290-5294; Endo, Y., Shibazaki, M., Nakamura, M., Takada, H., 1997. Contrasting effects of lipopolysaccharides (endotoxins) from oral black-pigmented bacteria and Enterobacteriaceae on platelets, a major source of serotonin, and on histamine-forming enzyme in mice. J. Infect. Dis. 175, 1404-1412]. In the present study, it was found that such shock was almost completely prevented in those mice in which platelets were displaced from the blood by Cl2MBP-liposomes. These results suggest that in the spleen the depletion of phagocytic macrophages may impair the function or structure of this organ. This may lead to the entry of platelets into the spleen in such large numbers as to reduce their level in the blood and result in their prolonged accumulation in the spleen. The Cl2MBP-liposome may be an excellent tool for the in vivo investigation of the role of platelets, as well as that of macrophages.

Intrahypothalamic perfusion of KP102 stimulates growth hormone release in goats

The hypothalamic actions of KP102 (also called GHRP-2) on the release of GH were studied in female goats. KP102 (10(-5) M) was perfused into the goat hypothalamus through a microdialysis probe (CMA/10 probe with a 4 mm membrane length) at a rate of 4 microl/min for 90 min, and plasma GH concentrations before and after perfusion were measured. The intrahypothalamic perfusion of 10(-5) M KP102 significantly stimulated GH release in goats (P<0.05). The GH levels began to rise after commencement of perfusion, and reached a maximum mean value at 180 min. The concentrations of GH at 165, 180, 195, 210, 225 and 240 min after commencement of perfusion of KP102 were significantly higher than the corresponding values for control animals (P<0.05). KP102 had no effect on GH pulse frequency, but it significantly increased the GH pulse amplitude after the perfusion (P<0.05). In contrast to KP102, intrahypothalamic perfusion of 10(-5) M GHRH had no effect on the stimulation of GH release in goats even if intravenous injection of 10(-5) M GHRH significantly stimulated GH release (P<0.05). These results suggest that KP102 may act partly on the hypothalamus to stimulate GH release in goats.

Abnormalities of pancreatic islets by targeted expression of a dominant-negative KATP channel

ATP-sensitive K+ (KATP) channels are known to play important roles in various cellular functions, but the direct consequences of disruption of KATP channel function are largely unknown. We have generated transgenic mice expressing a dominant-negative form of the KATP channel subunit Kir6.2 (Kir6.2G132S, substitution of glycine with serine at position 132) in pancreatic beta cells. Kir6.2G132S transgenic mice develop hypoglycemia with hyperinsulinemia in neonates and hyperglycemia with hypoinsulinemia and decreased beta cell population in adults. KATP channel function is found to be impaired in the beta cells of transgenic mice with hyperglycemia. In addition, both resting membrane potential and basal calcium concentrations are shown to be significantly elevated in the beta cells of transgenic mice. We also found a high frequency of apoptotic beta cells before the appearance of hyperglycemia in the transgenic mice, suggesting that the KATP channel might play a significant role in beta cell survival in addition to its role in the regulation of insulin secretion.