Differential scanning calorimetric studies on bovine serum albumin. IV. Effect of anionic surfactants with various lengths of hydrocarbon chain

Using defatted and SH-blocked bovine serum albumin (BSA), measurements of differential scanning calorimetry (DSC) have been made at pH 7 on the complexes of BSA and a series of sodium alkyl sulfates used were sodium decyl sulfate (SDeS), sodium octyl sulfate (SOS), sodium hexyl sulfate (SHS) and sodium ethyl sulfate (SES). Results obtained were compared with those on the system BSA-sodium dodecyl sulfate (SDS) studied previously. Two peaks P1 and P2 existed in the DSC curve of BSA. These peaks originate in the heat-induced transition of BSA. The pattern of DSC curve changed with the amount of the ligand added, i.e. with the molar mixing ratio ligand/BSA (1). The change for systems BSA-SDeS, BSA-SOS and BSA-SHS was qualitatively the same as that for the system BSA-SDS (2). Interestingly, SES, which is not a surfactant, interacts with BSA. The change for the system BSA-SES was qualitatively the same as that for the system BSA-Na2SO4. All alkyl sulfates suppressed the heat-induced transition at lower concentrations. A linear relationship was obtained for the plots of log(D/A)1 versus log CMC, where (D/A)1 is the molar mixing ratio of anionic surfactant (D) to BSA (A) at which the most heat-stable complex is formed. This suggests that the hydrophobic force has a serious effect on the formation of heat-stable complexes.

Severe hepatitis related to chemotherapy in hepatitis B virus carriers with hematologic malignancies. Survey in Japan, 1987-1991

BACKGROUND

Hepatitis B (HB) virus (HBV) infection is often reactivated, leading to severe hepatitis and death. Because the actual incidence of such complications is unknown, the authors surveyed hospitals to record the incidence of these complications and to identify clinical parameters that would possibly predict the development of hepatic complications.

METHODS

First, 250 hospitals, belonging to the Japanese Society of Clinical Hematology, were surveyed for hematologic patients with chronic hepatitis or those with asymptomatic hepatitis virus infection in whom severe hepatitis related to chemotherapy occurred between 1987 and 1991. Second, 117 hospitals that responded to the first questionnaire were surveyed for HBV carriers without severe hepatitis who were prescribed chemotherapy.

RESULTS

One-half the number of patients with severe hepatitis were HBV carriers. The incidence of severe hepatitis (52.7%) and the mortality rate (23.6%) were extremely high in HBV carriers. The incidence of severe hepatitis was significantly higher in patients with chronic hepatitis or those receiving corticosteroids (P < 0.05). The mortality rate was significantly lower in patients who were positive for hepatitis Be antigen (HBeAg) and negative for the antibody to HBeAg (anti-HBe), compared with findings in other patients (P < 0.05).

CONCLUSIONS

HBV infection is a major causal agent for severe hepatitis related to chemotherapy in Japanese individuals. Chemotherapy, including corticosteroids, to treat hematologic malignancies should be considered risky in HBV carriers, especially those with chronic hepatitis or serologies negative for HBeAg and positive for anti-HBe.

Microsatellite instability in sporadic human breast cancers

Human breast-cancer specimens from 100 patients were analyzed for microsatellite instability (referred to as replication error; RER) at 12 genomic loci on 7 chromosomes, and results were correlated with clinicopathologic characteristics. In 42 of 100 breast-cancer patients, we investigated whether RER was associated with the amplification of oncogenes and/or suppression of tumor-suppressor genes. Of the 100 patients, 8 (8%) were RER-positive at one or more chromosomal loci. The majority of RER-positive patients had early-stage disease with ER-positive tumors, suggesting that RER occurs early in breast tumorigenesis. However, no significant correlation was observed between RER and oncogenes or tumor-suppressor genes. Thus, the mechanism of RER in sporadic human breast cancer may be independent of the multi-step carcinogenesis caused by the alterations of oncogenes and tumor-suppressor genes.

High-risk HPV-positive human cancer cell lines show different sensitivity to cisplatin-induced apoptosis correlated with the p21Waf1/Cip1 level

We investigated the sensitivity and cell-cycle inhibitory gene expression of human papillomavirus (HPV) 16- and 18-positive human cancer cell lines after DNA damage induced by treatment with the anti-cancer drug cisplatin. Four HPV-positive cell lines (Caski, SiHa, HeLa and KB) were treated with cisplatin at various concentrations. Apoptotic cell death was observed in a dose-dependent manner in all cell lines treated with cisplatin; however, colony assay for chemosensitivity revealed that HeLa and KB cells (HPV 18-positive cell lines) were more sensitive than SiHa and Caski cells (HPV 16-positive cell lines). Northern blot analyses showed that p53 and p21Waf1/Cip1 mRNA were detectable in all untreated cells, and increasing amounts of these transcripts were identified in all cell lines treated with cisplatin. However, signals were more prominent in HeLa and KB, HPV 18-positive-cells. Immunohistochemical detection of p21Waf1/Cip1 protein showed that the p21-positive cells with apoptotic features were more distinct in KB and HeLa cells (HPV 18-positive) than in SiHa and Caski cells (HPV 16-positive). Our results show that there were differences in sensitivity to cisplatin among four types of high risk HPV-positive cells, possibly due to different levels of p21Waf1/Cip1 up-regulation by functional p53.

A new simple and rapid screening method for variant transthyretin-related amyloidosis

To screen for transthyretin (TTR) related amyloidosis rapidly and reliably, we have developed a new method using a centrifugal concentrator device and electrospray ionization mass spectrometry (ESI-MS). Only 50 microliters of serum is needed for the analysis. After preparation of the samples with anti-TTR antibody they were passed through a 1000 kDa cut off centrifugal concentrator which retained the antibody. By analyzing the obtained filtrate with ESI-MS, variant forms of TTR was detected. TTR (Met30), with a molecular weight 32.0 Da higher than the normal form of TTR, was found in all FAP patients examined. In 3 liver transplanted FAP patients, the abnormal peaks had disappeared. In conclusion, The TTR Met30 mutation was easily detected in serum samples by electrospray ionization mass spectrometry after centrifugal concentration. The proposed method is simple to perform, as no HPLC is required, and offers a possibility to screen populations for TTR related amyloidosis.

Autonomic dysfunction and anemia in neurologic disorders

The effect of autonomic dysfunctions on anemia in various neurological disorders, such as familial amyloidotic polyneuropathy (FAP) Type I, pandysautonomia, and Shy-Drager syndrome was examined. As a control, hemograms of patients with amyotrophic lateral sclerosis (ALS), which is known to be free from autonomic dysfunction, was compared with patients with the above neurological disorders. FAP and pandysautonomia patients showed significant anemia comparable with the severity of the autonomic dysfunctions. Shy-Drager patients exhibited mild anemia. However, in ALS patients, no such anemia was recognized at all even in the end stage of this disease. In pandysautonomia patients, hypoplastic bone marrow was recognized, which was quite consistent with the data previously reported in FAP patients. Human recombinant erythropoietin improved orthostatic hypotension as well as anemia in 4 FAP patients. These results suggest that autonomic dysfunction may be deeply connected with erythropoiesis.

Intracellular Ca2+ mobilization in cultured human mucosal microvascular endothelial cells from the nasal inferior turbinate

Human mucosal microvascular endothelial cells (HMMECs) were isolated and cultured from the mucosa of nasal inferior turbinates. These cells were identified by human factor-VIII antigen and UEA-I. We also investigated alterations in intracellular calcium concentration [Ca2+]i, in HMMECs using the Ca(2+)-sensitive dye fura-2. Depolarization by high K+ (150 mM) induced no changes in [Ca2+]i in HMMECs, thereby indicating the lack of voltage-dependent Ca2+ channels in these cells. Extracellular ATP increased [Ca2+]i in HMMECs both in the presence and absence of extracellular Ca2+. These results suggest that ATP may induce a release of Ca2+ from intracellular stores in HMMECs. Adenosine induced no changes in [Ca2+]i in HMMECs. It is thus likely that HMMECs obtained from the nasal inferior turbinate may carry P2-purinoceptors but not P1-purinoceptors.

Subcloning of three osteoblastic cell lines with distinct differentiation phenotypes from the mouse osteoblastic cell line KS-4

Three distinct osteoblastic cell lines (KS418, KS460, and KS483) were subcloned from the mouse osteoblastic KS-4 cells, which possessed the abilities not only to differentiate into mature osteoblasts, but also to support osteoclast differentiation in coculture with spleen cells. The order of the magnitude of the basal alkaline phosphatase (ALP) activity was KS483 > KS418 > KS460. KS483 cells were also more differentiated than KS418 and KS460 in terms of ALP activity and osteocalcin production, when cultured in growth medium containing 10% fetal bovine serum. In long-term culture, KS418 and KS483 apparently differentiated into mature osteoblasts and formed calcified nodules without addition of beta-glycerophosphate. Electron microscopic analysis demonstrated that calcification occurring in the nodules was initiated in the matrix vesicles as observed in bone formation in vivo. Nodule formation and mineral deposition occurred simultaneously in the presence of beta-glycerophosphate, but the former always preceded the latter without addition of beta-glycerophosphate. In contrast, KS460 cells did not show time-dependent increases of ALP activity, type I collagen expression and osteocalcin production, which were induced by treatment with recombinant osteogenic protein-1 (OP-1). The three cell lines similarly supported osteoclast differentiation in coculture with spleen cells in response to 1,25-dihydroxyvitamin D3. These results indicate that the three cell lines subcloned from the original KS-4 cells represent phenotypically distinct osteoblasts during osteoblast differentiation, but are equipped similarly with the capacity to support osteoclast differentiation. The subcloned cells of the KS-4 series may provide useful systems in which to study osteoblast differentiation and function.

Induction of Na+/myo-inositol cotransporter mRNA after focal cerebral ischemia: evidence for extensive osmotic stress in remote areas

Myo-inositol is one of the major organic osmolytes in the brain. It is accumulated into cells through an Na+/ myo-inositol cotransporter (SMIT) that is regulated by extracellular tonicity. To investigate the role of SMIT in the brain after cerebral ischemia, we examined expression of SMIT mRNA in the rat brain after middle cerebral artery occlusion, which would reflect alteration of extracellular tonicity. The expression of SMIT mRNA was markedly increased 12 h after surgery in the cortex of the affected side and lasted until the second day. Increased expression was also found in the contralateral cingulate cortex. Up-regulated expression was found predominantly in the neurons in remote areas, although nonneuronal cells adjacent to the ischemic core also expressed this mRNA. These results suggest that cerebral ischemia causes extensive osmotic stress in brain and that the neuronal cells respond to this stress by increasing SMIT expression.

The effect of anti-VLA-4 monoclonal antibody on eosinophil accumulation and leukotriene production in nasal mucosa

Eosinophil derived leukotrienes and platelet activating factor are known to cause nasal swelling. Toxic proteins induce nasal hyperreactivity to non-specific stimuli including histamine. Recent studies strongly suggest that very late activation antigen-4 (VLA-4) on the eosinophil surface plays a prominent role in the recruitment of eosinophils from blood vessels and eosinophil locomotion in inflammatory tissues. To test this hypothesis, we examined the effect of a monoclonal antibody (mAb) to VLA-4 on eosinophil accumulation in nasal mucosa after antigen challenge in a guinea pig model. Here we have demonstrated that the mAb depressed the eosinophil accumulation in nasal mucosa. In addition, we have shown that this mAb also inhibited eosinophil activation and leukotriene production. Our results raise a possibility that eosinophils might be activated during the journey from bloodstream to inflammatory tissues by the adhesion to endothelial cells and fibronectin. VLA-4 might act as a signalling as well as an adhesion receptor on eosinophils.

IFN-gamma has a protective role against thyroid-specific autoantibody production in severe combined immunodeficient (SCID) mice xenografted with Graves' thyroid tissue

We studied the effects of exogenous human IFN-gamma or neutralizing monoclonal antibody (mAb) to IFN-gamma on xenografted human Graves' thyroid tissue in severe combined immunodeficient (SCID) mice to investigate a possible role of IFN-gamma in the pathogenesis of human Graves' disease. Human thyroid tissues from four patients with Graves' disease were xenografted into SCID mice. Two weeks after xenografting, mice were divided into three groups with human IgG levels similar to each other. Mice in the first group were treated with human IFN-gamma daily for 6 weeks; mice in the second (similar) group were treated with an mAb to IFN-gamma; mice in the third group were given mouse IgG only (control group). Blood samples were taken every 2 weeks for human IgG and thyroid-specific autoantibodies (Tg-Ab, TPO-Ab, and thyroid-stimulating antibody). After 6 weeks' treatment, mice were killed, and the thyroid xenograft was examined for thyrocyte HLA-DR expression. Human IgGs were produced equally in all three groups; mice treated with IFN-gamma showed significantly lower amounts of thyroid autoantibodies than those in the control group. Thyrocyte HLA-DR expression was markedly increased in xenografts from mice with IFN-gamma administration. On the other hand, anti-IFN-gamma mAb injection caused only slight suppression of HLA-DR expression on xenografted thyroid cells. In conclusion, IFN-gamma may down-regulate the production of thyroid-specific autoantibodies but not human IgG, at least under these circumstances; there thus may be specific inhibitory effects of IFN-gamma against thyroid-specific autoantibody production of intrathyroidal plasma cells, and this animal model may help to elucidate the possible role of cytokines in the pathogenesis of Graves' disease.

Effects of purinoceptor agonists on cytosolic Ca2+ concentration in swine tracheal smooth muscle cells in culture

1. The effects of various purinoceptor agonists on intracellular Ca2+ concentration ([Ca2+]i) in swine tracheal smooth muscle cells in primary culture were examined to investigate the subtype of purinoceptors in these cells. 2. ATP (1 microM to 1 mM) concentration-dependently increased [Ca2+]i which was measured by monitoring the fluorescence signal of fura2. 3. alpha, beta-Me ATP at concentrations higher than 10 microM increased [ca2+]i in the presence of extracellular Ca2+. Responses to the drug were 12 +/- 5 and 61 +/- 4% of responses to ATP (100 microM) at 100 microM and 1 mM, respectively (n = 7). The response to 100 microM ATP was inhibited by 62% in the presence of 1 mM alpha, beta-Me ATP (n = 8), though the drug at concentrations lower than that did not affect the response to ATP. 4. ATP increased [Ca2+]i in the absence of extracellular Ca2+. The response to ATP in this condition was 40% of that in the presence of extracellular Ca2+ (n = 8). 5. Neither cibacron blue 3GA (10 microM) (n = 8) nor suramin (10 and 100 microM) (n = 10) affected the response to ATP (1 microM to 100 microM). 6. The rank order of potency in the absence of extracellular Ca2+ was UTP > ATP > adenosine 5'-o-(3-thiotriphosphate) > > ADP = alpha, beta-methylene adenosine 5'-triphosphate > 2-(methylthio)-adenosine 5'-(tetrahydrogen triphosphate). 7. UTP (1 microM to 100 microM) concentration-dependently increased inositol 1,4,5-triphosphate (IP3) production. 8. These results suggest that the increase in [Ca2+]i induced by purinoceptor agonists is mediated mainly via a nucleotide receptor in swine tracheal smooth muscle cells in primary culture.

Extraction of Schistosoma haematobium antigens from infected human urine and generation of potential diagnostic monoclonal antibodies to urinary antigens

Proteins in Schistosoma haematobium infected human urine were concentrated by precipitation with saturated ammonium sulphate 50% (v/v) and various fractions obtained at different stages of precipitation tested for presence of schistosome antigens (ShAgs) by dot-ELISA. The protein fraction (UP2S) obtained following two-times precipitation was found to contain high concentrations of ShAg. Fraction UP2S was dialysed against phosphate-buffered saline (pH 7.4) and further purified by Sephadex G-200 column chromatography. Two protein peaks were eluted of which the first peak UP2S(pkI) was found to contain high concentrations of ShAgs as determined by microplate-ELISA. The second peak UP2S(pkII) consisted of human urine proteins. Further analysis of UP2S(pkI) revealed that ShAgs were mainly in the form of immune complexes with human IgG, IgM, IgA, IgE and complement C3. The ShAgs in both UP2S and UP2S(pkI) were found to be active as they induced immune responses in mice which produced antibodies reactive with S. haematobium worm as well as soluble egg antigens (SEA). Pure ShAgs were obtained from UP2S following dissociation of immune complexes with a carbonate buffer (pH 11.42) and further purification on Sephadex G-200. Immunizations with UP2S led to the generation of MoAbs which could bind both SEA and UP2S.

The neutrophil as an information transmitter in tumor inhibition by a streptococcal biological response modifier, OK-432

Effective treatment of a rat transplanted ascites tumor by i.p. injection of a streptococcal biological response modifier, OK-432, was abrogated by selective in vivo depletion of neutrophils by a monoclonal antibody, RP-3. The mechanisms by which neutrophils participate in the therapeutic action of OK-432 were studied with Winn's assay using peritoneal exudate cells periodically obtained from rats i.p. injected with this biological response modifier. Intraperitoneal resident macrophages were first activated with OK-432, and within 3 h, tumor-inhibitory activity had moved to the early exuded neutrophils. However, 6 h after injection, exuded macrophages were the only cells involved in tumor inhibition. Considered together with other findings, it is likely that, in this system, neutrophils may transmit information from resident macrophages to exuded inflammatory macrophages in a series of responses induced by i.p. injection of OK-432.

Virulence in mice of Orientia tsutsugamushi isolated from patients in a new endemic area in Japan

Four strains of Orientia tsutsugamushi (KN-1, KN-2, KN-3 and GJ-1) isolated from patients in an area of Gifu Prefecture, Japan, in which tsutsugamushi disease is newly endemic, were examined for their virulence in mice. Among these, KN-1 (identified as Kawasaki type), GJ-1 (identified as Kuroki type) and KN-2 strains were found to be non-lethal for BALB/c mice as well as CH3/HeJ mice, even with high doses (10(6) x being the 50% mouse infectious dose). On the other hand, the KN-3 strain was found to be sufficiently virulent to kill BALB/c mice. Among the prototype strains (Gilliam, Karp and Kato), the Karp and Kato strains exhibited high virulence to mice, while the Gilliam strain killed only a susceptible strain of mouse. BALB/c mice infected with KN-1 and KN-2 strains showed significant splenomegaly and moderate ascites accumulation in the first week of infection, while these symptoms became prominent during the second week of infection using KN-3, Karp and Kato strains. After infection with the GJ-1 strain, these symptoms were not observed. Antibody responses induced by infections with highly virulent strains were lower than that with low or intermediate virulent strains.

Localization of the specific binding site for magnesium(II) ions in factor IX

We demonstrated recently that coagulation factor IX has a specific binding site(s) for Mg2+ ions, independent of the (Ca2+)-binding sites, and that binding of Mg2+ ions is very important for expression of the functional conformation of this protein. We report here the localization of this Mg2+-specific binding site. We prepared three Gla-containing fragments of bovine factor IX, namely GlaEGF(NC) (residues 1-144+286-296), GlaEGF(N) (1-83) and the Gla domain peptide (1-46). Fragments GlaEGF(NC) and GlaEGF(N) retained the ability to undergo a conformational change upon binding of Mg2+ ions in the presence of excess Ca2+ ions. This change could be detected by a conformation-specific antibody. Furthermore, the Gla domain peptide was capable of binding Mg2+ ions, as determined by the metal ion-induced quenching of the intrinsic fluorescence. It appears that the (Mg2+)-specific binding site of factor IX is located in the N-terminal Gla domain.

Molecular cloning and characterization of guinea pig Fc gamma RIII: expression but not function is independent of the gamma chain of Fc epsilon RI

We have isolated two cDNA clones encoding the guinea pig receptor for the Fc portion of IgG2 (Fc gamma 2R) from a guinea pig peritoneal macrophage cDNA library. Analysis of the predicted amino acid sequence of the one cDNA clone indicated that the guinea pig Fc gamma 2R is a type I transmembrane protein and has approximately 72% DNA sequence homology and approximately 57% protein sequence homology with the human Fc gamma RIII. Therefore, we propose that the guinea pig Fc gamma 2R is referred to as guinea pig Fc gamma RIII. The most important finding in this report is that the obtained cDNA directed the cell surface expression of the Fc gamma 2R on COS-7 cells without association with the gamma chain of the high-affinity IgE receptor (Fc epsilon RI gamma) which is required for human and mouse Fc gamma RIII to be expressed on the cell surface. Furthermore, we demonstrated that the endocytosis activity of Fc gamma RIII is dependent upon the association with Fc epsilon RI gamma, suggesting that Fc epsilon RI gamma is involved in the functions of guinea pig Fc gamma RIII. The other clone was found to lack the sequence encoding transmembrane and cytoplasmic domains, suggesting the presence of a soluble form of guinea pig Fc gamma RIII. Northern blot analysis and RT-PCR showed that a transmembrane form of guinea pig Fc gamma RIII was expressed in peritoneal macrophages, but not in neutrophils in spite of the fact that they express Fc gamma 2R, indicating that the Fc gamma 2R on neutrophils is a product of a distinct gene.

Electrophysiological background of individual variability in electrical defibrillation efficacy

This study was performed to test whether heart-to-heart variability of defibrillation efficacy is attributable to differences in postshock refractory state of nondepolarized myocardium. In 30 anesthetized dogs, a localized potential gradient was created using 1-16 V of stimulus across a pair of platinum plate electrodes on the right ventricle (5-mm interelectrode distance). The postshock recovery interval (PSRI) of the relatively refractory myocardium directly adjacent to the excited area was estimated by measuring the recovery interval after an appropriately timed field stimulus. The transcardiac defibrillation threshold (DFT) was also determined. The results showed that DFT normalized by the weight of the heart was inversely correlated with the PSRI measured with a field stimulus of 6 V (local shock intensity approximately 5 V/cm) or more (6 V: r = -0.502, P < 0.005; 16 V: r = -0.635, P < 0.0005). This observation suggests that variability of defibrillation efficacy in intact hearts is largely due to differences in the postshock refractory state of the nondepolarized myocardium.

Use of a split dura for revascularization of ischemic hemispheres in moyamoya disease

A new technique of indirect revascularization using the dural arterial supply to provide donor vessels is presented together with the results of an assay performed to determine the angiogenic activity of the dura. At surgery, a portion of the dura near the branches of the middle meningeal artery was split into outer and inner layers, and the split surface of the outer layer was attached to the cortical surface. This procedure, combined a with standard encephaloduroarteriosynangiosis, was applied to 25 hemispheres in 18 patients with pediatric moyamoya disease (mean age 6 years). All of the patients were symptom free by 1.5 years after surgery. The follow-up period ranged from 1 to 12 years (mean 6.5 years). Thirteen (81%) of 16 patients were able to lead normal lives and three were mildly handicapped due to mental retardation that existed preoperatively. Postoperative superselective angiograms demonstrated effective cortical revascularization through the dural arteries as well as from the scalp arteries. A histological study of the dura in cases of moyamoya disease showed an increased number of blood vessels in the outer layer. Angiogenic activity determined by chorioallantoic membrane assay was higher in the split surface of the dura than in the internal surface of the dura (the natural interface between the dura and cortex). The split duroencephalosynangiosis described in this report is a useful addition to indirect revascularization techniques, allowing extension of the area of revascularization in the ischemic hemispheres of patients with moyamoya disease.

Pheochromocytomas: tendency to degenerate and cause paroxysmal hypertension

Eighty-four patients with pheochromocytoma underwent surgery during the 13-year period from 1981 to 1994. These patients were divided into three groups according to the degree of parenchymal degeneration, which was estimated by preoperative dynamic computed tomography (CT) scans and resected specimens: solid group, cystic group, and highly cystic group. The relation between the degree of parenchymal degeneration and the clinical variety, size of the tumor, predominant plasma catecholamine, and type of blood pressure disturbance was analyzed. There were 39 cases of solid pheochromocytoma, 37 cases of cystic tumor, and 8 cases of highly cystic pheochromocytoma. The maximal mean diameters for each group were as follows: 5.1 +/- 2.3, 6.8 +/- 3.0, and 7.9 +/- 3.2 cm, respectively. Of the tumors < 3 cm in diameter, 84% were solid; when the tumors were >/= 6 cm in diameter, approximately 50% were cystic and 20% highly cystic. Of the adrenal pheochromocytomas, 60% were degenerated; 79% of the extraadrenal tumors were solid. Of the epinephrine-secreting tumors, 70% were degenerated, and 55% of the norepinephrine-secreting tumors were solid. The clinical pattern of hypertension was related to the degree of degeneration: In the paroxysmal hypertension group 87% of the tumors were degenerated, and in the sustained hypertension group 69% were solid. We therefore believe that parenchymal degeneration of pheochromocytoma is highly correlated with the tumor diameter, location of the tumor, secreted catecholamine, and clinical pattern of hypertension.

Improvement of intestinal toxicity of 5-fluorouracil by conagenin, a low molecular immunomodulator

The effect of conagenin (CNG) on intestinal toxicity induction by 5-fluorouracil (5-Fu) was investigated. In mice given sublethal doses of 5-Fu (50mg/kg, i.v.) for 5 consecutive days, a decrease in body weight and diarrhea accompanied with hemorrhaging of the duodenum, atrophy of cecum and reduced small intestine length appeared. The administration of CNG in combination with 5-Fu inhibited thoe side effects induced by 5-Fu. Although all mice given 5-Fu alone were died within 13 days, 3 out of 10 mice treated with CNG survived for more than 21 days. The cytotoxicity of 5-Fu was not affected by CNG in vitro. The antitumor activity of 5-Fu was improved by CNG in increasing the number of surviving mice.