Evidence of a sophisticatedly heterogeneous population of human umbilical vein endothelial cells

Induction and promotion of angiogenesis play a role in a diverse range of physiologic and pathophysiologic processes that are especially relevant to the field of regenerative medicine. For assessing vasculogenesis and neo-angiogenesis, identifying angiogenic factors, angiocrine factors, and vascular niche, facilitating tissue-repair and tumor growth, efficiently generating induced pluripotent stem cells, and coculturing with organ-specific stem cells, isolation and characterization of the subpopulation of human umbilical vein endothelial cells (HUVECs) and their endothelial progenitor cells (EPCs) are needed. In this study, primary HUVECs were collected from fresh umbilical cords and fractionated and characterized with the use of flow cytometry. Clonal colony assay showed that endothelial colony-forming units in culture frequently existed in fresh HUVECs. Antigenic profiling demonstrated that undifferentiated EPCs in HUVECs had normal endothelial marker CD31 with a subpopulation of cells positive for hematopoietic stem cell marker CD34 and c-Kit. With continuing passages, EPC markers CD34 and vascular endothelial growth factor receptor 2 expression decreased dramatically. Moreover, a distinct subpopulation with different proliferative capability and angiogenesis from the early-passage HUVECs was shown. In conclusion, it is possible to isolate accurately and to enrich EPCs or hematoangioblast-like cells from a heterogeneous population of HUVECs, and to explore the differential process with flow cytometry for further investigations.

Fluorescent labeling and visualization of human induced pluripotent stem cells with the use of transcription activator-like effector nucleases

BACKGROUND

The visualization of induced pluripotent stem (iPS) cells with the use of fluorescent techniques is useful for the in vivo evaluation of iPS-derived functional cells following differentiation and distribution of the transplanted cells. The data obtained from the fluorescently labeled iPS cells would lead to amelioration and validation of protocols directing the differentiation of iPS cells into functional cells. In this study, we established enhanced green fluorescent protein (EGFP)-labeled iPS cells to enable their easy visualization.

METHODS

Human iPS cells were transfected with (a) 2 transcription activator-like effector nuclease (TALEN) vectors targeted to the adeno-associated virus integration site 1 (AAVS1) locus and (b) the targeting vector carrying the homology arms, EGFP gene, and a drug-selection marker.

RESULTS

Several puromycin-resistant clones were obtained after transfection of the targeting vector and corresponding TALEN-expressing vectors. EGFP expression in these clones was observed with the use of a fluorescent microscope. Clones were examined for specific recombination, which revealed precise targeting at the AAVS1 locus. Furthermore, EGFP protein expression was sustained after directed differentiation into a hepatic lineage.

CONCLUSIONS

We were successful in evaluating the behavior of iPS-derived hepatic cells. The data suggest that genomic knock-in at the AAVS1 locus is suitable for long-term observation of iPS-derived cells. Manipulation of the iPS genome can also be applied for the purification of hepatic cells during iPS cell differentiation by introducing the fluorescent protein under the regulation of a hepatic cell-specific promoter. Another application involves gene correction of iPS cells from patients with hepatic disease for regenerative medicine.

Identification of proliferating human hepatic cells from human induced pluripotent stem cells

Mass-scale production of hepatocytes from human induced pluripotent stem cells (iPSCs) with functional properties of primary hepatocytes is of great value in clinical transplantation for liver failure as well as in facilitating drug development by predicting humanized drug metabolism profiles. In this report, we generated human hepatocyte-like cells from human iPSCs with the use of a stepwise protocol. Aiming at future clinical and industrial application, it is important to determine the suitable stage of iPSC-derived hepatic cells that possess high proliferative capacity to intensively expand the hepatic cells. Ki67 immunostaining showed that human iPSC-derived hepatic endoderm cells contained Ki67(+) cells at the highest level in the middle stage of hepatic differentiation, suggesting that the abundance of proliferating hepatic progenitor cells exists in this stage. Extensive expansion and differentiation of human iPSC-derived hepatic progenitors will provide future perspectives in transplantation therapy and drug development.

Elastic cartilage reconstruction by transplantation of cultured hyaline cartilage-derived chondrocytes

Current surgical intervention of craniofacial defects caused by injuries or abnormalities uses reconstructive materials, such as autologous cartilage grafts. Transplantation of autologous tissues, however, places a significant invasiveness on patients, and many efforts have been made for establishing an alternative graft. Recently, we and others have shown the potential use of reconstructed elastic cartilage from ear-derived chondrocytes or progenitors with the unique elastic properties. Here, we examined the differentiation potential of canine joint cartilage-derived chondrocytes into elastic cartilage for expanding the cell sources, such as hyaline cartilage. Articular chondrocytes are isolated from canine joint, cultivated, and compared regarding characteristic differences with auricular chondrocytes, including proliferation rates, gene expression, extracellular matrix production, and cartilage reconstruction capability after transplantation. Canine articular chondrocytes proliferated less robustly than auricular chondrocytes, but there was no significant difference in the amount of sulfated glycosaminoglycan produced from redifferentiated chondrocytes. Furthermore, in vitro expanded and redifferentiated articular chondrocytes have been shown to reconstruct elastic cartilage on transplantation that has histologic characteristics distinct from hyaline cartilage. Taken together, cultured hyaline cartilage-derived chondrocytes are a possible cell source for elastic cartilage reconstruction.

The effect of spine postures on the hydrodynamic drag in Epinephelus ongus larvae

Laboratory behavioural observation and computational fluid dynamics (CFD) analysis were conducted to examine whether the movement of the elongated dorsal and pelvic spines changed the hydrodynamic drag in white-streaked grouper Epinephelus ongus larvae. The behavioural observation in the tank revealed that the larvae extended the dorsal and pelvic spines during passive transport and retracted during swimming; the angles of the dorsal and pelvic spines in relation to the anteroposterior axis were larger during the passive transport (mean ± S.D. = 28.84 ± 14.27 and 20.35 ± 15.05°) than those during the swimming (mean ± S.D. = 2.59 ± 5.55 and 0.32 ± 6.49°). The CFD analysis indicated that the relative hydrodynamic drag acting on the larvae was approximately 1.25 times higher when the spines were extended (passive transport) than when the spines were retracted (swimming), suggesting that the E. ongus larvae have an ability to adjust their hydrodynamic drag depending on the behavioural context.

Self-formation of vascularized hepatic tissue from human adult hepatocyte

BACKGROUND

Recent study has demonstrated the important role of endothelial-mesenchymal interactions in 3-dimensional self-organization of immature progenitor populations with the use of mimicking of organogenesis. Here, we show that the same principle can be applicable to adult mature cells, ie, human adult hepatocytes (hAHs).

METHODS

We cultivated hAHs with fluorescence-labeled human mesenchymal cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) in micro-well culture plates and observed them for 9 days. Fluorescence microscopy imaging analyses were performed to evaluate the internal structures of generated 3-dimensional tissues. Maintenance of in vitro protein production capacity was examined with the use of enzyme-linked immunosorbent assay (ELISA).

RESULTS

hAHs started to self-organize into 3-dimensional tissue with the use of coculturing with hMSCs and HUVECs. Live imaging analyses showed that endothelial cells started sprouting inside the generated tissues after 2 days of culture. ELISA showed that human albumin production capacity was improved with the use of coculture compared with hAHs-only culture after 9 days.

CONCLUSIONS

We demonstrated that 3-dimensional vascularized hepatic tissue could be generated from hAHs by reconstituting endothelial-mesenchymal interactions. Future studies are needed to evaluate the therapeutic potential of vascularized hepatic tissue transplantation, and this may pave a new way to establish a new transplantation modality as an alternative to hepatocyte transplantation.

Highly efficient generation of definitive endoderm lineage from human induced pluripotent stem cells

BACKGROUND

Although hepatocytes can be an option for liver transplantation, the shortage of donor organs continues to worsen. Since the development of induced pluripotent stem (iPS) cell technology, it is eagerly anticipated to produce functional elements from pluripotent stem cells. These functional cells differentiated from iPS cells could be used for transplantation, drug screening, and in vitro toxicology.

METHODS

Human iPS cells are maintained on Mitomycin C-treated mouse embryonic fibroblast layers in DMEM-Ham F12-based medium supplemented with Knockout Serum Replacement, nonessential amino acids, 2-mercaptoethanol, and Glutamax. Differentiation of human iPS cells into a definitive endodermal lineage was induced with PRMI 1640 medium supplemented with B27 and 100 ng/mL human activin A. Two B27 supplements were examined with and without insulin. Furthermore, the PI3 kinase inhibitor LY294002 was used to examine the effect of inhibiting insulin signaling.

RESULTS AND DISCUSSION

We established efficient induction of definitive endodermal differentiation from iPS cells. Quantitative analysis revealed efficient (93.03 ± 2.74%) differentiation of human iPS cells into definitive endoderm cells using B27 minus insulin. This protocol may contribute as a fundamental technique to promote human iPS studies to develop cellular sources for transplantation.

Human elastic cartilage engineering from cartilage progenitor cells using rotating wall vessel bioreactor

Transplantation of bioengineered elastic cartilage is considered to be a promising approach for patients with craniofacial defects. We have previously shown that human ear perichondrium harbors a population of cartilage progenitor cells (CPCs). The aim of this study was to examine the use of a rotating wall vessel (RWV) bioreactor for CPCs to engineer 3-D elastic cartilage in vitro. Human CPCs isolated from ear perichondrium were expanded and differentiated into chondrocytes under 2-D culture conditions. Fully differentiated CPCs were seeded into recently developed pC-HAp/ChS (porous material consisted of collagen, hydroxyapatite, and chondroitinsulfate) scaffolds and 3-D cultivated utilizing a RWV bioreactor. 3-D engineered constructs appeared shiny with a yellowish, cartilage-like morphology. The shape of the molded scaffold was maintained after RWV cultivation. Hematoxylin and eosin staining showed engraftment of CPCs inside pC-HAp/ChS. Alcian blue and Elastica Van Gieson staining showed of proteoglycan and elastic fibers, which are unique extracellular matrices of elastic cartilage. Thus, human CPCs formed elastic cartilage-like tissue after 3-D cultivation in a RWV bioreactor. These techniques may assist future efforts to reconstruct complicate structures composed of elastic cartilage in vitro.

Self-organization of human hepatic organoid by recapitulating organogenesis in vitro

BACKGROUND

Careful orchestration among endodermal epithelial, endothelial, and mesenchymal cells initiate liver organogenesis prior to vascular function. Nonparenchymal endothelial or mesenchymal cells not only form passive conduits, but also establish an organogenic stimulus. Herein, we have evaluated the potential roles of primitive endothelial and mesenchymal cells toward hepatic organization in vitro.

METHODS

To track the cellular movements and localization, we retrovirally transduced enhanced green fluorescence protein and kusabira orange into human fetal liver cells (GFP-hFLCs) and human umbilical vein endothelial cells (KO-HUVECs), respectively. GFP-hFLCs were cocultivated with KO-HUVECs and human mesenchymal stem cells (hMSCs) under conventional two-dimensional (2D) conditions.

RESULTS

Even under 2D culture, fetal liver, endothelial, and mesenchymal cells self-organized into a macroscopically visible three-dimensional (3D) organoid. Time-lapse confocal imaging showed dynamic cellular organizations of GFP-hFLCs and KO-HUVECs. Endothelial cells organized into patterned clusters wrapping fetal liver cells, forming vessel-like lumens inside. Mesenchymal cells supported the generated organoid from outside.

CONCLUSION

Generation of whole organ architecture remains a great challenge so far. Our preliminary results showed that recapitulation of primitive cellular interactions during organogenesis elicit the intrinsic self-organizing capacity to form hepatic organoids. Future studies to define precise conditions mimicking organogenesis may ultimately lead to the generation of a functional liver for transplantation and for other applications such as drug development.

Generation of functional human vascular network

BACKGROUND

One of the major obstacles in regenerating thick, complex tissues such as the liver is their need for vascularization, which is essential to maintain cell viability during tissue growth and to induce structural organization. Herein, we have described a method to engineer a functional human vascular network.

METHODS

Enhanced green fluorescence protein-labeled human umbilical vein endothelial cells (GFP-HUVECs) were cocultivated with kusabira orange-labeled human mesenchymal stem cells (KO-hMSCs) inside a collagen/fibronectin matrix. Premature vascular network formation was visualized by fluorescence microscopy imaging. Furthermore, constructs prevascularized in vitro were implanted into a transparency window in immunodeficient mice.

RESULTS

Following several days of cultivation, GFP-HUVECs formed vessel-like structures that were stabilized by pericytes differentiated from KO-hMSCs. After implantation in vivo, the patency of human vascular structures was proved by rhodamine dextran infusion. These functional vascular structures remained for over 2 months.

DISCUSSION

Vascularization is the key challenge to organ generation. We successfully generated human vascular networks inside a matrix. Integration of parenchymal cells using our engineering technique should facilitate future efforts to reconstitute vascularized human organ systems in vitro.

Stimulation of hepatocyte growth factor production by ascorbic acid and its stable 2-glucoside

Hepatocyte growth factor (HGF), a cytokine which is generally produced by mesenchymal cells, has mitogenic, motogenic and morphogenic activities in epithelial cells and it also has tumor-suppressing activities. Induction of HGF production may be involved in organ regeneration, wound healing and embryogenesis. We examined the effects of ascorbic acid (AsA), which stimulates the proliferation of fibroblasts, and its stable derivative, 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G), on HGF production by human skin fibroblasts. Basal HGF secretion was significantly stimulated by more than 0.1 mM AsA or AA-2G. Both vitamins synergistically enhanced HGF secretion stimulated by growth factors such as epidermal growth factor (EGF), platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF), cholera toxin and other inducers. Induction by EGF or bFGF was most markedly potentiated by the vitamins. HGF production by the KG-1 human leukemia cell line was also augmented by AsA or AA-2G. Another stable AsA derivative, ascorbic acid 2-phosphate (AA-2P) effectively promoted basal and EGF-induced HGF secretion by the fibroblasts, but ascorbic acid 2-sulfate (AA-2S) was much less effective. Intracellular AsA levels increased after the addition of AA-2G and AA-2P as well as AsA, but not after AA-2S. The effect of AA-2G was completely abrogated by the simultaneous addition of castanospermine, an alpha-glucosidase inhibitor, suggesting that the active form of AA-2G is AsA. Constitutive and EGF-induced HGF gene expression was also up-regulated after adding AsA or AA-2G to the cells. These results indicated that AsA acts alone or in synergy with several inducers to stimulate the production and gene expression of HGF in human skin fibroblasts and that the stable AsA derivative AA-2G is as effective as AsA in promoting HGF production.

Induction of hepatocyte growth factor/scatter factor by interferon-gamma in human leukemia cells

Induction of hepatocyte growth factor/scatter factor (HGF/SF) may be one of the critical steps in organ regeneration, wound healing, and embryogenesis. We previously reported the production of HGF/SF from various human leukemia cell lines and a high level of the growth factor in blood and bone marrow plasma from patients with various types of leukemia. We determined here the effects of hematopoietic cytokines on HGF/SF production in human leukemia cell lines, KG-1, a myeloid cell line, and RPMI-8226, a B cell line. Interferon (IFN)-gamma remarkably stimulated HGF/SF production in both cell lines at concentrations of more than 0.1 or 1 IU/ml. IFN-alpha and IFN-beta were as effective as IFN-gamma in RPMI-8226 cells, but less than IFN-gamma in KG-1 cells. HGF/SF gene expression in KG-1 cells was also up-regulated by IFN-gamma. Granulocyte colony-stimulating factor (G-CSF), granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-5 and IL-6 had no effect on HGF/SF production in the 2 leukemia cell lines. We also determined the effects of HGF/SF inducers known for human fibroblasts on the growth factor production in leukemia cells. Out of phorbol 12-myristate 13-acetate (PMA), cholera toxin, IL-1 beta, and tumor necrosis factor (TNF)-alpha, the former three were as effective as IFN-gamma in KG-1 cells, but only TNF-alpha stimulated HGF/SF production in RPMI-8226 cells, whose effect was less than those of IFN-alpha, IFN-beta, and IFN-gamma. The effect of IFN-gamma in KG-1 cells was synergistic with that of PMA. In contrast with the effect in leukemia cells, HGF/SF induction by IFN-gamma in human skin fibroblasts was much less than that by PMA or cholera toxin. These results indicated that IFN-gamma is a potent inducer of HGF/SF in human leukemia cells. This finding suggests the presence of a homeostatic control mechanism in liver regeneration and repair: hepatic injury, DNA synthesis inhibition, or apoptosis caused by IFN-gamma is subsequently overcome by cytokine-induced HGF/SF, a potent promoter of liver DNA synthesis.

Induction of hepatocyte growth factor in human skin fibroblasts by epidermal growth factor, platelet-derived growth factor and fibroblast growth factor

Hepatocyte growth factor (HGF) is a potent mitogen for rat and human hepatocytes in primary culture and appears to be the physiological hepatotrophic factor that triggers or modulates liver regeneration. Regulation of HGF gene expression and the protein production in human skin fibroblasts was examined. Addition of epidermal growth factor (EGF), platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), acidic fibroblast growth factor (aFGF) and transforming growth factor-alpha (TGF-alpha) to confluent cultures of the cells markedly stimulated HGF secretion from the cells. The stimulating effect of EGF, PDGF and bFGF was further investigated. The effect of all three growth factors was maximal at 3-30 ng/ml and was accompanied by an increase in HGF mRNA levels. The mRNA levels were not elevated at 5 h but were at 10 h or more after addition of EGF. The levels of HGF mRNA in fibroblasts treated with the optimal doses of EGF, PDGF, bFGF, aFGF and TGF-alpha for 24 h were 6, 4, 5, 4 and 5 times that of control cultures incubated in medium only, respectively. The growth factor-induced HGF mRNA expression and HGF secretion was inhibited by addition of TGF-beta 1 or dexamethasone. Pretreatment with a high dose of phorbol 12-myristate 13-acetate (PMA), which causes down-regulation in protein kinase C (PKC) activity and PMA-induced HGF secretion, did not reduce the effects of the growth factors on HGF mRNA expression and HGF secretion, but rather enhanced them.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of hepatocyte growth factor is up-regulated through activation of a cAMP-mediated pathway

Hepatocyte growth factor (HGF) is a multifunctional cytokine with mitogenic, motogenic, morphogenic, and tumor-suppressing activities. Despite the broad spectrum of its biological activities, HGF is most likely the physiological hepatotrophic factor that triggers or modulates liver regeneration. Regulatory mechanisms for HGF production are crucial for understanding the control of liver regeneration. We previously reported that HGF production by human skin fibroblasts is stimulated by a protein kinase C (PKC)-mediated pathway. We determined here whether gene expression and production of HGF in human skin fibroblasts can be induced via activation of a cAMP-mediated pathway. HGF secretion by the cells was markedly stimulated by the cAMP-elevating agents, forskolin, cholera toxin, prostaglandin E2 (PGE2), and 3-isobutyl-1-methylxanthine, as well as by the membrane-permeable cAMP analogues, 8-bromo-cAMP and dibutyryl cAMP. The dose-response curves of induction of HGF secretion by cholera toxin and forskolin were nearly parallel with those of the intracellular cAMP levels. HGF mRNA levels did not significantly increase at 5 and 10 h, but increased considerably 15 h or more after the addition of cholera toxin. Forskolin, 8-bromo-cAMP, and PGE2 also caused appreciable up-regulation of HGF gene expression with a similar time course. Although human skin fibroblasts of various origins secreted variable amounts of HGF, the cAMP-elevating agents and the cAMP analogues caused a very marked increase in HGF production in all of them. The agents also enhanced highly active HGF secretion by MRC-5 human embryonic lung fibroblasts. Dexamethasone and transforming growth factor-beta 1, which inhibit PKC-mediated HGF secretion, down-regulated HGF mRNA expression and HGF production in the cells treated with the cAMP-elevating agents and the cAMP analogues. These results indicate that HGF expression in human skin fibroblasts is stimulated by activation of a cAMP-mediated pathway.

Effect of long-term ethanol feeding on the restoration process of acute necrotizing pancreatitis induced in rats

This study was conducted to elucidate the possible influence of long-term peroral administration of alcohol on the repair process of acute necrotizing pancreatitis. Male Wistar rats fed with balanced diet were divided into two groups. The first group had free access to 15% ethanol, and the second group, the control group, has access to water instead. After fifty weeks, acute necrotizing pancreatitis was induced in rats by infusing 0.4% lysolecithin into their pancreatic duct. In the course of pancreatitis, pancreatic enzymes in serum, enzymes and protein in pancreas, and DNA synthesis in pancreas in both groups, changed in the same way. Histologically, interstitial edema, necrosis of parenchyma, infiltration of inflammatory cells, and formation of tubular complex were observed. Most of these histological changes of pancreas in both groups disappeared in twenty days and pancreas was repaired almost completely. These findings suggest that the repair process of acute necrotizing pancreatitis is not affected by preceding long-term intake of alcohol.

Characterization of amylase linked immunoglobulin G to distinguish human salivary and pancreatic isoamylases

An immunoglobulin G of the kappa type linked to salivary amylase was identified in the serum of a patient with colon cancer and persistent hyperamylasemia. The binding site on the immunoglobulin in the complex is located in F(ab')2 portion. The purified IgG recombined only with purified human salivary amylase, and could be used to separate human isoamylases.

Tumor-associated antigen defined by a monoclonal antibody against neuraminidase-treated human cancer cells

A monoclonal antibody, MH-A6, was produced by immunization with a human gastric cancer cell line, MKN 74, treated with neuraminidase. The antigen defined by the monoclonal antibody was detected on various tumor tissues and a limited number of normal tissues in immunoperoxidase assay, and the expression of MH-A6 antigen was not influenced by neuraminidase treatment except for some cases of tumor tissues. Interestingly, neuraminidase treatment enhanced binding of the antibody on some adenocarcinomas, but diminished binding of the antibody on squamous cell carcinomas. Both treatment of the immunizing tissues with trypsin and periodic acid diminished binding of the antibody. In isolation of MH-A6 antigen from MKN 74 cells by the monoclonal antibody coupled-affinity column, the epitope exists on molecules with molecular weights of 30,000 and 72,000, and with an acidic pH range in two-dimensional electrophoresis. CEA and CA 19-9 activities were not detected in purified MH-A6 antigen by solid-phase radioimmunoassay, and the reactivity of the MH-A6 antibody with CEA and CA 19-9 was not detected in enzyme-linked immunosorbent assay. Hemagglutination observed between erythrocytes (Lewisa, Lewisb, or NE-treated) and anti-Lewisa, anti-Lewisb sera, or anti-T-agglutinin (peanut lectin), respectively, was not inhibited by MH-A6 antigen. The results suggest that MH-A6 antigen is a tumor-associated antigen, probably glycoprotein, and different from CEA, CA 19-9, Lewisa, Lewisb, and Thomsen-Friedreich (T) antigen.

Non-selective inhibition of insulin and glucagon release by xenogeneic islet cell surface antibodies

The influence of xenogeneic islet cell surface antibodies (ICSA) on the hormonal secretion of non-B islet cells has not been completely elucidated. Accordingly, we investigated the influence of xenogeneic antiserum on glucagon release from A cells, as representative of non-B islet cells, together with other characteristics of the antiserum. Anti-islet cell sera were produced in rabbits by xenogeneic immunization with dispersed hamster islet cells. Rabbit anti-hamster islet cell surface antibodies were detected both qualitatively by indirect immunofluorescence analyses and quantitatively by 125I-protein A radioligand assay. However, antiserum did not induce cell surface immunofluorescence on rat or mouse islet cells. As a result of evaluation of the specific cytotoxicity using 51Cr release assay, antiserum was observed to induce a significantly higher release of 51Cr compared with that of normal rabbit serum in complement-dependent antibody-mediated cytotoxicity. Both glucose-stimulated insulin and arginine-stimulated glucagon release were suppressed by xenogeneic antiserum not only in the presence but also in the absence of complement. It is concluded, therefore, that xenogeneic antiserum has a relative species specificity and non-selectively binds to islet cells in contrast with the non-species specificity and preferential binding to pancreatic B cells of human ICSA, although heterogeneity in ICSA-positive sera has been suggested.

[A report on the epidemiology and the clinical features of the patients with chronic pancreatitis in Hokkaido District]

We carried out through questionnaires the second survey on the epidemiology and the clinical features of chronic pancreatitis in Hokkaido district. Chronic pancreatitis was diagnosed in 258 patients in 19 hospitals during the period April 1977 to December 1984. The ratio of male cases to females was 2.7:1.0 and the average age was 53.9. Alcoholic abuse, observed in 55% of the patients, was a main causative factor. A half of the patients was diagnosed on the basis of pancreatogram and/or image of the pancreas (ultrasonogram and computed tomogram). The incidence of chronic pancreatitis in the second survey was about fourfold over that diagnosed during the period January 1970 to March 1977 in the first survey. Such an increasing number of the patients with chronic pancreatitis in Hokkaido district was considered to be resulted from the difference between two surveys in epidemiological aspects and diagnostic criteria. The proportion of female patients and alcoholic patients was calculated to be increasing. The frequency of the patients diagnosed in a relatively early stage was supposed to be also increasing, because in the second survey a new item (pancreatogram, ultrasonogram and computed tomogram) was added to the diagnostic criteria (histological evidence, pancreatic calcification and definitive disturbance of exocrine pancreatic function) in the first survey. Based on whether alcoholic abuse was causative factor or not, the patients were divided into two groups and the clinical manifestations of both groups were compared.(ABSTRACT TRUNCATED AT 250 WORDS)

The usefulness of serum PABA measurement after BT-PABA administration in the diagnosis of chronic pancreatitis

We examined the maximal serum PABA concentration within 3 hrs (MS-PABA) and the 6 hr urinary PABA recovery (6 hr U-PABA) after BT-PABA administration, PABA excretion index, and chymotrypsin secretory response to caerulein-secretin stimulation in ten control subjects and fifteen patients with chronic pancreatitis diagnosed on the basis of pancreatograms. The results suggested that MS-PABA can distinguish the patients with definite irregular dilatation of the main pancreatic duct from the controls, but not those with localized irregular dilatations of the side branches from the controls. MS-PABA showed a significant correlation with 6 hr U-PABA, PABA excretion index, chymotrypsin output and bicarbonate output. This modified method was shown to be useful in the diagnosis of chronic pancreatitis with unequivocally abnormal pancreatograms and/or markedly decreased chymotrypsin secretion. This modification will serve to simplify the BT-PABA test by eliminating urinary collection and shortening the procedure time.

Insulin and glucagon response of the diabetic Chinese hamster in the Asahikawa colony

The relationship between pancreatic hormone content and pattern of hormone release has not been completely elucidated because of heterogeneity in diabetes. Accordingly, this study was performed to establish the relationship, using spontaneously diabetic Chinese hamsters in the Asahikawa colony, a newly discovered experimental model resembling insulin-deficient diabetes in humans. As a result of investigations of insulin and glucagon responses to glucose or arginine in vivo and in vitro using isolated islets obtained by the collagenase procedure, a decreased insulin response and paradoxical glucagon response to glucose, and an excessive glucagon response to arginine were found in the diabetic animals. While the yield of isolated islets tended to decrease, a decreased pancreatic insulin content and increased pancreatic glucagon content were found as the diabetic state advanced. It may be suggested, therefore, that the relationship between pancreatic hormone content and pattern of hormone release in diabetic animals in the Asahikawa colony is based on the disruption of islets, disruption or dysfunction of B-cells and hyperplasia or hypertrophy of A-cells by some cause genetically determined.

Paradoxical glucagon response in perifused islets of the diabetic Chinese hamster

Dynamic insulin and glucagon response to glucose was examined in the perifusion system to investigate the relationship between pancreatic hormone content and the pattern of hormone secretion in diabetic Chinese hamsters of the Asahikawa colony (CHA). Isolated islets of normals and diabetics from the CHA were perifused. When the medium was changed to high glucose (500 mg/dl), a low insulin response and paradoxical glucagon response were seen in diabetics compared with normals. Positive correlations were found between pancreatic insulin and the amount of perifusate insulin, and glucagon content and glucagon release, respectively. It is suggested, accordingly, that pancreatic hormone content is related to the amount of hormone release in CHA. A negative correlation between the amount of perifusate insulin and glucagon release was found. It is suggested, therefore, that an impaired suppression of glucagon release in the diabetic CHA animals could be attributed at least to insulin deficiency. These findings agree with the histological discovery of decreased B-cells and increased A-cells in the diabetic islets. Both decreased B-cells and islet numbers could be the cause of the low insulin response to glucose. Increased numbers of A-cells with hyperfunction resulting from local insulin deficiency could be the cause of the paradoxical glucagon response.

Elevation of plasma high density lipoprotein-cholesterol in spontaneously diabetic Chinese hamsters

The aim of this study is to define the change of plasma high density lipoprotein-cholesterol (HDL-C) in the spontaneously diabetic Chinese hamsters in the Asahikawa colony (CHA). These animals were divided into two groups according to fasting plasma glucose level; non-diabetic group and diabetic group. Plasma HDL-C was measured by a microliters-scale ultracentrifugal method using an RPL-42T rotor (Hitachi Koki Co.). The diabetic hamsters had hypoinsulinemia and hyperlipidemia. Plasma HDL-C in the diabetic group was significantly elevated as compared with the non-diabetic group. A significant positive correlation was observed in both groups between plasma HDL-C and total cholesterol. The male hamsters tended to have higher plasma HDL-C and total cholesterol levels than the female hamsters in either group. Moreover, an electrophoretic analysis showed that there was some relative increase in plasma very low density lipoprotein, low density lipoprotein and high density lipoprotein (HDL) in the diabetic hamsters. An ultracentrifugal analysis showed that plasma chylomicron appeared only in the diabetic hamsters. The heterogeneity of particle size of HDL was found by gradient gel electrophoresis. The apparent average molecular weight of HDL was approximately 265,000 in either group. It is concluded that plasma HDL-C increased with the advance of hyperglycemia and hyperlipidemia in insulin-deficient diabetic hamsters and that there was sex difference in the hamsters for plasma HDL-C and total cholesterol.

[The effect of oral synthetic protease inhibitor (FOY 305) on endocrine pancreas and carbohydrate and lipid metabolism in normal and streptozotocin-induced diabetic rats]

The effect of long-term oral synthetic protease inhibitor (FOY 305) administration on fasting blood sugar (FBS), body weight, glucose tolerance, plasma insulin and glucagon levels, pancreatic insulin and glucagon contents, hepatic enzyme activities, and plasma lipids in normal and streptozotocin (STZ)-induced diabetic rats was studied. Normal rats treated with oral FOY 305 for 9 weeks were found to have pancreatic hypertrophy and decreased body weight gain as compared with the untreated normal controls. FBS, glucose tolerance, plasma insulin and glucagon levels, pancreatic insulin and glucagon contents, and plasma lipids were uninfluenced in FOY 305 treated normal rats. STZ-induced diabetic rats treated with oral FOY 305 were found to have decreased FBS for 5 weeks after the beginning of FOY 305 administration as compared with the untreated diabetic controls, whereas at the 7th and 9th week after treatment there was no difference in FBS between FOY 305 treated and untreated diabetic rats. In the metabolic balance observed at the 4th week after treatment, a slight improvement of the diabetic state was found in FOY 305 treated diabetic rats. There was no apparent difference in the blood sugar curve and insulin response following oral glucose load between diabetic rats treated for 7 weeks and untreated diabetic rats. All the rats were sacrificed after 9 weeks of treatment. Diabetic rats treated with oral FOY 305 for 9 weeks showed pancreatic hypertrophy and decreased plasma glucagon level and decreased pancreatic glucagon content as compared with the untreated diabetic controls, whereas there was no difference in body weight, plasma insulin level and pancreatic insulin content between FOY 305 treated and untreated diabetic rats. Furthermore, oral FOY 305 treatment improved hyperlipidemia in STZ-induced diabetic rats and also significantly improved the hepatic pyruvate kinase and phosphoenlpyruvate carboxykinase activities of diabetic rats. These improvements might partly be due to a decreased pancreatic content and secretion of glucagon and/or a direct action of the synthetic PI, FOY 305 to tissues.

[Acute necrotizing pancreatitis caused by the injection of lysolecithin into the pancreatic duct in the rat. Its natural course and effect of drugs on rate of survival]

Acute experimental pancreatitis was induced by retrograde injection of 0.15 ml of 0.8% lysolecithin into the pancreatic duct of Wistar rats. This procedure was always followed by severe necrosis of pancreatic parenchyma, bloody ascites and numerous fat necroses in the abdominal cavity. Histologically, at the 30th minutes after the induction of pancreatitis, spotty necrosis of pancreatic tissues and marked edema of interstitium were observed. The necrosis gradually expanded accompanying bleeding and inflammatory cell infiltration till the 60th hours. At the 72nd hours after the induction there were the replacement of the necrotic tissue with the fibroblasts, the neogenesis of the ductular epithelium and the formation of acinus-like structure. Among the changes of extrapancreatic organs those of the lung were pronounced. Macroscopically, from the 12th hours stiff and reddish lung frequently occurred. Histologically, micro-macroatelectasis, edema and cell infiltration of the alveolar wall, and the stricture of the bronchioles were observed. In this experimental pancreatitis, the rate of survival was about 50% within 48 hours and about 30% within 72 hours, respectively. Continuous intravenous infusion of cytidine diphosphate choline at a dose of 300 mg/kg/day and intravenous injection of methylprednisolone at a dose of 60 mg/kg/day significantly improved the rate of survival within 24 hours and within 30 hours, respectively.

[Antineoplastic effect of UFT therapy (uracil-FT-207 combination therapy) on experimental pancreatic cancer transplanted in the pancreas and subcutaneous region]

The pancreatic duct cell adenocarcinoma induced by di-isopropanol nitrosamine could be easily and repeatedly transplanted into the subcutaneous or pancreatic tissues of the homologous animals. We established a tumor bearing animal design in which tumor tissues were transplanted simultaneously into subcutaneous and pancreatic tissues. At the first week after the transplantation, the animals were divided into three groups: In FT group FT-207 was given at a dose of 15 mg/kg/day, in UFT group FT-207 and uracil were given at a dose of 3 mg/kg/day and; 6.7 mg/kg/day (molar ratio; 1:4), respectively and in control group a solvent of FT-207 was given. In all groups the drugs were administrated orally for ten days. The size of tumors transplanted in subcutaneous and pancreatic tissues increased more slowly in FT and UFT groups, as compared with that of control group. The inhibitory effect on tumor growth observed in UFT group was more striking than that in FT group. No major side effects were observed in all groups. At the fourth weeks after subcutaneous and intrapancreatic transplantation, the animals were divided into two groups: In FT group FT-207 was given at a dose of 30 mg/kg and in UFT group FT-207 and uracil were given at a dose of 30 mg/kg and 67.2 mg/kg, respectively. In both groups the drugs were given orally, and at one hour after the administration all the animals were killed to determine 5-FU concentration in various tissues. The 5-FU concentrations of subcutaneous and intrapancreatic transplanted tumor tissues were significantly higher in UFT group than those in FT group. UFT therapy, therefore, seems to be hopeful for the treatment of human pancreatic cancer.

Effect of long term alcohol feeding on the pancreas in rat

To elucidate the pathophysiological process of alcoholic pancreatitis, chronic alcohol intoxication was made in Wistar rats on balanced diet giving 20% ethanol freely for 60 weeks. The control rats received water. Histological picture of the pancreas, hormonal activity in the mucosa of upper digestive tract and the nature of pancreatic juice were examined in every 15th week. The results were as follows. 1) No histological changes were noted in the pancreas of control group. In the ethanol group, morphological abnormalities of the pancreas appeared after 30 weeks. Of the histological findings, the changes on the ductal system such as dilatation of pancreatic duct, plug formation in the ductal lumen and periductal fibrosis were significant. 2) The long term ethanol administration tended to decrease the amounts of gastrin, secretin and cholecystokinin contained in the gastrointestinal mucosa. 3) Regardless of the histological changes of the pancreas, almost no changes were noted in the bicarbonate and protein concentration during the experimental period of 60 weeks. From the above results, a mechanism obstructing pancreatic ductal system is considered to be important in the pancreatic lesions by alcohol rather than a mechanism of stimulating pancreatic exocrine secretion.

Reserve capacity of bicarbonate secretion in chronic pancreatitis

When secretin was given by continuous intravenous infusion in the control subjects, the dose of secretin inducing maximal bicarbonate output was found to be around 6.0 CHR U/kg/hr. Then the pancreatic exocrine secretory response to sequential standard (1.2 CHR U/kg/hr) and augmented (6.0 CHR U/kg/hr) dose of secretin was studied in the controls, in patients with chronic pancreatitis and in its suspected cases. This new method for exocrine pancreatic function did not offer advantage for the diagnosis of well established chronic pancreatitis. But from the results obtained in suspected chronic pancreatitis it was supposed that the decline of increasing rate of bicarbonate output with augmentation of dose and the decrease of response to augmented dose of secretin might be one of functional disorders occurred in the early stage of chronic pancreatitis.

Secretin-like bioactivity in the duodenal mucosa in patients with peptic ulcer and chronic pancreatitis

Biopsy specimens of the duodenal mucosa were assayed to determine their secretin-like activity in 9 controls, 9 patients with gastric ulcer, 19 patients with duodenal ulcer, 4 patients with gastric and duodenal ulcer, and 13 patients with chronic pancreatitis. The bioassay of secretin was done on the pancreatic secretion in anesthetized rats. The sensitivity was in the orcer of 0.0625 CHR unit/rat (4 ng/rat). In the range between 0.0625 and 0.5 CHR units a satisfactory dose dependency was recognized. The following results were obtained. 1) The level of duodenal mucosal secretin-like activity in patients with gastric ulcer was the same as that in the controls, but was elevated in 32% of the patients with duodenal ulcer, 50% of those with gastric and duodenal ulcer, and 8% of those with chronic pancreatitis. 2) The high level of secretin-like activity noted in patients with duodenal ulcer was suspected to be related to the hypersecretion of gastric acid which is characteristic of this disease, but there was no correlation between gastric acid secretion and secretin-like activity in the duodenal mucosa.

The significance of the sweat test in chronic pancreatitis

In order to study the disposition which is thought to be latent in chronic pancreatitis, we investigated the sweat chloride concentration of 95 normal subjects, 43 cases of chronic pancreatitis, 12 cases of cholelithiasis, 15 cases of peptic ulcers, 16 cases of hepatic diseases and 23 cases of diabetes mellitus with the sweat test, using the method of pilocarpine iontophoresis. We obtained the following results. (1) In normal subjects, the sweat chloride concentration was inclined to rise gradually with age from childhood to adulthood; the mean value of sweat chloride concentration was 30.0 mEq/liter in adults from 20 years old, and the upper limit was about 60 mEq/liter. (2) The mean value of sweat chloride concentration was 60.0 mEq/liter in chronic calcifying pancreatitis; this value was markedly higher than that of control subjects of the same age (p is less than 0.001). (3) The mean value of sweat chloride concentration in cholelithiasis, peptic ulcer and hepatic diseases did not differ significantly from control subjects. The mean value of sweat chloride concentration in diabetes mellitus was significantly higher than that of control subjects (p is less than 0.01), but was significantly lower than that in chronic pancreatitis (p is less than 0.01). (4) It was supposed that some cases of chronic pancreatitis have a congenital disposition toward abnormal secretion of sweat glands and epithelium in the pancreatic duct, resembling cystic fibrosis, and this disposition leads easily to pancreatic disorders when the individual is exposed to various external factors.