Effect of Bifidobacterium bifidum fermented milk on Helicobacter pylori and serum pepsinogen levels in humans.

Helicobacter pylori infection is an important risk factor for gastric diseases. Some probiotics are useful for suppressing H. pylori infection. Bifidobacterium bifidum YIT 4007 can improve the experimental gastric injury in rats and the disease stages on the gastric mucosa in peptic ulcer patients. We evaluated the fermented milk using a clone (BF-1) having the stronger ability to survive in the product than this parent strain to clarify the in vitro suppressive effect of BF-1 on H. pylori and the in vivo efficacy of BF-1 fermented milk on H. pylori and gastric health. In the mixed culture assay of BF-1 and H. pylori, the number of pathogens was decreased such that it was not detected after 48 h in the Brucella broth with a decrease in pH values. In the cell culture experiment with human gastric cells, the H. pylori infection-induced IL-8 secretion was suppressed by the preincubation of BF-1. In a human study of 12-wk ingestion (BF-1 group, n = 40; placebo group, n = 39) with a randomized double-blind placebo-control design, the H. pylori urease activity and gastric situation were evaluated using a urea breath test (UBT) and the serum pepsinogen (PG) levels as biomarkers for inflammation or atrophy, respectively. In the H. pylori-positive subjects, the difference (DeltaUBT) of the UBT value from the baseline value in the BF-1 group (n = 34) was lower than that in the placebo group (n = 35) at 8 wk. The baseline UBT values showed a negative correlation with DeltaUBT values at 8 and 12 wk in the BF-1 group but not in the placebo. In the PG-positive subjects classified by the PG test method, the BF-1 group was lower in DeltaUBT values than the placebo group at 8 and 12 wk. In the active gastritis class by PG levels, the BF-1 group was lower in their DeltaUBT values than the placebo at 8 and 12 wk. The PG I levels in the BF-1 group were lower than the placebo at 12 wk. The PG II levels in the BF-1 group did not change during the ingestion period, but the placebo was increased. The PG I/II ratios slightly decreased from baseline at 12 and 20 wk in the BF-1 and placebo groups. These patterns were also observed in the H. pylori-positive subjects. The improving rates of upper gastrointestinal symptomatic subjects and total symptom numbers in the BF-1 group were higher than those in the placebo. These results indicate that BF-1 fermented milk may affect H. pylori infection or its activity, gastric mucosal situation, and the emergence of upper gastrointestinal symptoms.

Nonlinear pharmacokinetics of CPT-11 in rats.

The pharmacokinetics of a new water-soluble derivative of camptothecin. 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11), and its major metabolite, 7-ethyl-10-hydroxycamptothecin (SN-38), was investigated after i.v. administration of 1 to 40 mg/kg of CPT-11 to rats. The plasma concentration of CPT-11 decreased biexponentially. The area under the concentration-time curve increased nonlinearly as the dose increased. SN-38 was found in the plasma, bile, urine, and feces. The SN-38 level was maintained at 0.06 to 0.08 micrograms/ml for 0.5 to 5.5 h depending on the dose, followed by exponential decay. Thirty-three to 58% of the CPT-11 was excreted without metabolism into the bile and urine for 24 h. SN-38 was mainly excreted into the bile. Analysis of the clearance has shown nonlinear pharmacokinetics which was due to metabolic processes such as the conversion of CPT-11 to SN-38.

Metabolism and pharmacokinetics of the camptothecin analogue CPT-11 in the mouse.

A new water-soluble derivative of camptothecin, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11), did not exhibit potent antitumor activity in vitro against experimental tumor cells. The 50% effective doses of CPT-11 against KB and L1210 cells were 1100 and 5500 ng/ml, respectively. These values were markedly higher than those of camptothecin (CPT, 0.98 and 3.7 ng/ml) or 7-ethyl-10-hydroxycamptothecin (SN-38, 0.37 and 3.6 ng/ml). CPT-11 was found to be converted into SN-38 in mouse serum. In vitro incubation of CPT-11 in mouse serum or tissue homogenate enhanced the growth-inhibitory activity much more than that expected from the concentration of CPT-11. This enhancement of the activity coincided with that expected from the SN-38 concentration in incubated serum or homogenate, though the contribution of CPT-11 could not be refuted. SN-38 is considered to play a major role in the antitumor activity when CPT-11 is incubated in serum or homogenate. The plasma CPT-11 concentration decreased biexponentially after i.v. administration of CPT-11 into mice with a biological half-life of 0.8 to 1.1 h. The area under the plasma CPT-11 concentration-time curve showed dose dependency. The SN-38 concentration decreased for the first 30 min after administration and was then maintained for a few hours at about 0.1 microgram/ml after i.v. administration of 20 and 40 mg/kg of CPT-11 followed by the log-linear terminal phase with a half-life of about 2 h which was independent of the dose. It is suggested that the maintenance of plasma SN-38 concentration might be necessary for it to exhibit antitumor activity in vivo.

Intravenous administration of irinotecan elevates the blood beta-glucuronidase activity in rats.

7-Ethyl-10-hydroxycamptothecin (SN-38) is the active metabolite of an anticancer drug, irinotecan (CPT-11). Severe late diarrhea is the dose-limiting toxic effect of CPT-11. This diarrhea has been examined regarding biliary excretion and deconjugation of SN-38 glucuronide by the enzyme beta-glucuronidase (beta-GL) in intestinal microflora. Prompted by the enzymological and structural similarity of CPT-11 to organophosphorus and carbamate insecticides, we studied the effect of CPT-11 on blood beta-GL activity in rats. The i.v. injection of CPT-11 in rats significantly elevated their plasma beta-GL activity (with phenolphthalein glucuronide as a substrate) at doses of 10 and 40 mg/kg, with peak activity observed 2-3 h after administration. SN-38 lactone and carboxylate had no effect on the plasma beta-GL level. The enhancement of the activity was also observed in serum using SN-38 glucuronide as a substrate. The serum beta-GL levels showed a close correlation between these substrates. The enhancement of plasma (serum) beta-GL activity is suggested to be a result of the release of beta-GL from liver microsomes. Serum and microsomal carboxylesterase were not significantly affected by CPT-11 administration.

Antitumor activity of 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothec in, a novel water-soluble derivative of camptothecin, against murine tumors.

The search for new water-soluble analogues of camptothecin (CPT) with higher activity and less toxicity has led to the development of a novel compound, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin (CPT-11), which showed significant antitumor activity against a broad spectrum of experimental tumor models by i.p., i.v., or oral administration. When its activity against L1210 was compared with that of CPT and known derivatives, CPT-11 was most effective, giving the highest maximum increase in life span (ILS) and showing good activity over a wide dose range. The antitumor activity of CPT-11 was shown against tumors not only in the ascites form but also in the solid form. Included among the more susceptible murine tumors are S180, Meth A fibrosarcoma, Lewis lung carcinoma, Ehrlich carcinoma, MH134 hepatoma, mammary carcinoma of C3H/HeN mice, L1210, and P388 leukemia. Probable cures of these tumors were induced frequently by CPT-11. The antitumor activity of CPT-11 against i.p.-implanted L1210 was superior to that of Adriamycin in maximum ILS, the number of cured mice, and the therapeutic ratio. CPT-11 at a dose of 100 mg/kg produced an ILS in excess of 300% with five of six mice surviving tumor free, and effected 100% tumor regression at 200 mg/kg, whereas the optimum dose of Adriamycin, 12.5-25 mg/kg, brought about 114-129% ILS with one of six mice surviving. The acute toxicity of CPT-11 was extremely low, particularly in the case of oral administration. CPT-11 is expected to be clinically useful.

Role of colony-stimulating activity in antitumor activity of Lactobacillus casei in mice.

Wide-ranging differences were observed between the antitumor activities of 23 lactobacilli (13 species; 23 strains) and their capacities to elevate the level of serum colony-stimulating activity (CSA) by intraperitoneal administration in mice, and a good correlation existed between the two activities. The mechanism of enhanced production of CSA by administration of Lactobacillus casei YIT 9018 (LC 9018), one of the bacteria that had the strongest activities, and the role of CSA in antitumor activity of LC 9018 were studied. Colony-stimulating activity in the washing fluid from the peritoneal cavity of mice that had been administered LC 9018 intraperitoneally was elevated at 3 to 24 h after the injection, and CSA was also detected at elevated levels in the serum of the mice 6 to 12 h after injection. The cells responsible for the production of CSA after stimulation with LC 9018 seem to be the resident macrophages at the site of administration, because the resident macrophages of mice lavaged 1 h after an intraperitoneal administration of LC 9018 released CSA when they were cultured in vitro. Moreover, resident peritoneal macrophages of normal mice cultured with LC 9018 in vitro also produced CSA. Similar results were obtained with athymic nude mice, and the CSA-inducing activity of LC 9018 was diminished in the mice pretreated with carrageenan, which is selectively toxic to mature macrophages. Bone marrow cells matured to macrophages and polymorphonuclear cells by culture with the CSA induced by LC 9018 for 7 days. These matured macrophages showed strong antitumor activity both in vivo and in vitro. These results suggest that CSA plays important roles in the antitumor activity of LC 9018: it enhances not only the multiplication of committed precursor cells for macrophages and polymorphonuclear cells, but also the functional maturation of the precursor cells for macrophages which serve as potent effectors for tumor cells.

Sequence and expression of a gene encoding a ribosomal protein S4 homolog from Drosophila melanogaster.

We describe a Drosophila melanogaster cDNA clone encoding an amino acid (aa) sequence 75% identical to human ribosomal protein S4 (RPS4). The D. melanogaster RPS4 has 260 aa, if the NH2-terminal methionine is removed after translation of the mRNA. The mRNA for the protein is about 1 kb in length and is detected throughout the developmental stages tested (i.e., embryo, larva, pupa and adult). The cDNA clone hybridizes to two sites on the X chromosome, 1B1-2 and 3A3-6.

Effect of oral administration of Lactobacillus casei on alloxan-induced diabetes in mice.

The effect of Lactobacillus casei (LC) on the onset of alloxan (AXN)-induced diabetes in 7-week-old BALB/c mice were examined. It was observed that the mice given a diet containing 0.1% or 0.05% LC or orally administered LC showed significantly decreased incidence of diabetes induced by intravenous injection of AXN and that the plasma glucose level was slightly lower than that in the control group. The body weight in the LC-treated groups was higher than that in the control group, although the food intake weights were almost the same. Pathological analysis revealed that the AXN-induced disappearance of insulin-secreting beta-cells in the islets of Langerhans was strongly inhibited in the LC-treated groups. It was also shown that the serum nitric oxide level was maintained at a normal level in LC-treated mice, whereas the level in the control group was increased by AXN administration. Taken together, these findings suggest that oral administration of LC to AXN-treated BALB/c mice contributed to the reduction of diabetes and the increase in plasma glucose level.

Prevention of onset in an insulin-dependent diabetes mellitus model, NOD mice, by oral feeding of Lactobacillus casei.

The effect of Lactobacillus casei (LC) on the onset of diabetes in an insulin-dependent diabetes mellitus model, nonobese diabetic (NOD) mice, were examined. From the age of 4 weeks, female NOD mice were fed a diet of either standard laboratory chow (n = 12) or the same chow containing 0.05% weight heat-killed cells of LC (n = 12), and the onset of diabetes was thereafter recorded. The incidence of diabetes in the control group (10/12) was significantly higher than that in the LC-treated group (3/12) (p < 0.01). Pathological analysis in the LC-treated group revealed strong inhibition of the disappearance of insulin-secreting beta cells in Langerhans islets caused by autoimmune disease. The proportion of CD45R+ B-cells in the spleen was increased and that of CD8+ T-cells in spleen cells was decreased in the LC-treated group. Analysis of cytokine production revealed lower interferon-gamma production in the LC-treated group compared to the control group, while the interleukin (IL)-2 production was higher. The levels of IL-4, IL-5, IL-6 and IL-10 in the LC-treated group were somewhat higher than in the control group. Taken together, these findings clearly demonstrated that oral feeding of LC to NOD mice effectively inhibited the occurrence of diabetes and regulated the host immune response.

Radioprotection of mice by a single subcutaneous injection of heat-killed Lactobacillus casei after irradiation.

Treatment of whole-body gamma-irradiated mice with a preparation of Lactobacillus casei (LC 9018) immediately after irradiation caused a sustained increase in serum colony-stimulating activity which was followed by an enhanced repopulation of granulocyte-macrophage colony-forming cells in the femoral marrow and spleen. Numbers of blood leukocytes, erythrocytes, and platelets were increased earlier in the treated mice than in the controls, and the survival rate was elevated significantly. The radioprotective effect was dependent on the dose of LC 9018 as well as on the dose of radiation. These results demonstrate the value of LC 9018 for the treatment of myelosuppression after radiotherapy or radiation accidents.

Structure of 6-deoxytalose-containing polysaccharide from the cell wall of Bifidobacterium adolescentis.

The isolation and analysis of the cell wall and the polysaccharide-glycopeptide complexes of Bifidobacterium adolescentis YIT4011 are presented. Polysaccharide-glycopeptide complexes, PS-GP1 and PS-GP2, were solubilized from the cell wall by treatment with N-acetylmuramidase. PS-GP1 and PS-GP2 were found to be composed of glucose, 6-deoxytalose and a small amount of glycopeptide. The products of Smith degradation of the PS-GPs had no glucose-containing fraction, but were composed of 1,2/1,3-linked 6-deoxytalose. Furthermore, a second Smith degradation of this fraction yielded trisaccharide-glyceraldehyde. These results and methylation analysis led to the conclusion that PS-GP1 or 2 has a repeating unit of----3)6dTal(beta 1----3)6dTal(beta 1----3)6dTal(beta 1----2)-6dTal(alpha 1----2)6dTal(alpha 1----2)6dTal(alpha 1-, and that glucose residues are linked to position C-3 of the 2-O-substituted 6-deoxytalose residues.

Structural studies of cell wall polysaccharides from Bifidobacterium breve YIT 4010 and related Bifidobacterium species.

The chemical compositions of the cell walls obtained from 8 strains in 5 species of Bifidobacterium were analyzed. These cell walls were shown to be composed of peptidoglycan and polysaccharide moieties. Some variations with respect to contents of neutral sugars and content of phosphorus were observed with some cell wall preparations from the same species. The neutral polysaccharides in cell walls of 4 strains of Bifidobacterium (B. bifidum YIT 4007, B. breve YIT 4010, B. infantis YIT 4025, and B. longum ATCC 15707) were purified and their chemical structures were analyzed. One of these polysaccharides, obtained from B. breve YIT 4010, was analyzed in detail by GLC, 1H- and 13C-NMR spectroscopic analyses, methylation, Smith degradation and acetolysis, and the results suggested the following structure for the repeating unit of the polysaccharide: (Formula: see text).

Kinetic studies on the plasminogen activation by the staphylokinase-plasmin complex.

A pure complex of staphylokinase and plasmin was prepared by affinity chromatography with lysine-Sepharose, which enabled the simple analysis of the mechanism of plasminogen activation by staphylokinase. We used a truncated staphylokinase (SAK), which lacks the 10 amino acid residues at the NH2 terminal of native staphylokinase. The purity of this complex was confirmed by the native PAGE profile. Image analysis of the SDS-PAGE profile revealed that the molar ratio of plasmin and SAK in the complex was about 1:1. Using this SAK-plasmin complex, the kinetic parameters for the activation of Glu- or Lys-plasminogen were determined. The kinetic constant, kcat/Km, obtained when Lys-plasminogen was used as a substrate was approximately 10 times higher than that obtained when Glu-plasminogen was used. This plasminogen activation property of the SAK-plasmin complex was comparable to that of other plasminogen activators, such as streptokinase, urokinase, and tissue-type plasminogen activator (t-PA). This SAK-plasmin complex will simplify the elucidation of plasminogen activation by SAK. Through kinetic studies, the fibrin specificity and participation of plasminogen activator inhibitor will be clarified.

Structure of polysaccharide-peptidoglycan complex from the cell wall of Lactobacillus casei YIT9018.

The isolation and analysis of the polysaccharide-peptidoglycan complexes of Lactobacillus casei YIT9018 are presented. Two polysaccharide-peptidoglycan complexes, PS-PG1 and PS-PG2, were solubilized from the heat-killed cell by treatment with N-acetylmuramidase. PS-PG1 was composed of glucose, rhamnose, and small amount of galactose and glucosamine. PS-PG2 was composed of glucose, rhamnose, galactosamine, and glucosamine. The ratio by weight of these fractions was about 1:8. PS-PG2 was analyzed in detail. Smith degradation and deamination of this complex yielded oligosaccharide units. The results of methylation analysis of these units and intact PS-PG2 led to the most probable structure of PS-PG2: (formula; see text)

Sex-dependent toxicity of a novel acyl-CoA:cholesterol acyltransferase inhibitor, YIC-C8-434, in relation to sex-specific forms of cytochrome P450 in rats.

YIC-C8-434 is a novel inhibitor of acyl coenzyme A:cholesterol acyltransferase (ACAT). To clarify the toxicity of YIC-C8-434, the compound was given orally to Sprague-Dawley rats for 28 days at 0, 4, 20, 100, or 500 mg/kg/day. The toxicity of the drug differed significantly between male and female rats. In female rats treated at 500 mg/kg, many symptoms including moribund condition, suppression of weight gain and food consumption, abnormal blood chemistry, and decreases in organ weights (thymus, ovaries, and uterus) were observed. In male rats by contrast, no significant toxicity was observed at any dose. After a single administration of YIC-C8-434 at 500 mg/kg, female rats had a higher blood concentration of the compound than male rats. Little elimination of YIC-C8-434 was observed in female rats on analysis of drug-elimination kinetics. Furthermore, the metabolism of YIC-C8-434 was analyzed using rat hepatic microsomal preparations from both sexes. Consistent with the observations in vivo, hepatic microsomes from male rats better metabolized YIC-C8-434 than those from females. In addition, the metabolism of YIC-C8-434 by hepatic microsomes from male rats was blocked by SKF525A, a P450 inhibitor. Inhibition experiments using anti-rat CYP1A1, CYP1A2, CYP2B1, CYP2C11, CYP2E1, CYP3A2, and CYP4A1 antisera indicated that CYP3A2 played the predominant role in the metabolism of YIC-C8-434 in rats. Since there is less CYP3A2 in the liver of female than male rats, the involvement of CYP3A2 in YIC-C8-434 metabolism has implications for the sex-related metabolic activity and toxicity of YIC-C8-434.

Inhibition of spontaneous and experimental metastasis by a new derivative of camptothecin, CPT-11, in mice.

The antimetastatic effect of a new water-soluble derivative of camptothecin, 7-ethyl-10-(4-(1-piperidino)-1-piperidino) carbonyloxy-camptothecin (CPT-11), were examined in several metastatic murine tumor systems. Intravenous (i.v.) injection of CPT-11 into BALB/c mice inhibited lung metastasis by i.v. inoculated, metastatic colonic adenocarcinoma 26 (C26) cells, C26NL-17, in BALB/c mice. This treatment was also effective in C57BL/6 mice against lung metastasis by i.v. inoculated B16-F10 and B16-BL6 cells, highly metastatic variants of the B16 melanoma. Furthermore, intraperitoneal (i.p.) injection of CPT-11 significantly inhibited the growth of C26NL-22 cells, a highly metastatic variant of C26, inoculated subcutaneously (s.c.) into the left front footpads of BALB/c mice. Also, i.p. or i.v. injection of CPT-11 effectively inhibited the growth of 3LL tumors inoculated s.c. into the hind footpads of C57BL/6 mice. Moreover, following s.c. inoculation of either C26NL-22 or 3LL cells, combined surgical excision of the primary tumor and either i.p. or i.v. CPT-11 injections given before or after surgery markedly inhibited the formation of pulmonary metastases. These results show that a new derivative of camptothecin, CPT-11, has a potent inhibitory effect against both spontaneous and experimental lung metastasis.

Antitumor effect of CPT-11, a new derivative of camptothecin, against pleiotropic drug-resistant tumors in vitro and in vivo.

CPT-11, a new derivative of camptothecin, was effective against tumor cells, especially vincristine (VCR)-and adriamycin (ADM)-resistant P388 leukemia, compared to either VCR or ADM. The drug showed superior chemotherapeutic effects over VCR and ADM in sensitive P388 leukemia-bearing mice, and was also effective in VCR- and ADM-resistant P388 leukemia-bearing mice. These latter survival advantages with CPT-11 were almost equal to those obtained by CPT-11 against sensitive P388 leukemia. CPT-11 was found to be effective against human tumor cells, especially various pleiotropically drug-resistant human tumor lines, compared to VCR and ADM. CPT-11 should be considered for further development as a new chemotherapeutic agent potentially effective against pleiotropically drug-resistant tumors.

Modified irinotecan hydrochloride (CPT-11) administration schedule improves induction of delayed-onset diarrhea in rats.

PURPOSE: Clinically, diarrhea is the major dose-limiting toxicity of irinotecan hydrochloride (CPT-11). Using a rat model, we attempted to decrease the incidence of delayed-onset diarrhea by modifying the administration schedule of CPT-11, and studied the pharmacokinetics in this model in relation to the incidence of diarrhea. METHODS: CPT-11 (total dose, 240 mg/kg) was administered intravenously (i.v.) to rats according to various schedules, and the incidence of delayed-onset diarrhea was monitored. RESULTS: Administration of CPT-11 at a dose of 60 mg/kg once daily for four consecutive days induced severe diarrhea, while at 30 mg/kg twice daily at an interval of 9 h (daily dose 60 mg/kg) for four consecutive days alleviated the diarrheal symptoms, and at 30 or 40 mg/kg once daily for eight or six consecutive days, respectively. diarrhea was hardly induced. With the first schedule, mucosal impairment of the cecal epithelium was observed, including wall thickening, edema, decrease in crypt number and size, and formation of pseudomembrane-like substance, whereas these changes were less severe with the second schedule and were hardly observed with the other two schedules. The areas under the plasma and cecal tissue concentration-time curves (AUCpla and AUCcec), the maximum plasma concentrations (Cmax) and the biliary excretions of CPT-11 and its metabolites, 7-ethyl-10-hydroxycamptothecin (SN-38) and SN-38 glucuronide (SN-38G) in rats depended on the daily dose of CPT-11. Exceptionally, CPT-11 Cmax was significantly lower and SN-38 AUCcec was larger in the animals treated at 30 mg/kg twice daily than in those treated at 60 mg/kg once daily. CONCLUSION: These results suggested that the duration of exposure to both CPT-11 and SN-38 of the intestinal epithelium and CPT-11 plasma Cmax are closely related to the incidence and severity of CPT-11-induced delayed-onset diarrhea in rats.

Antitumor activity of a camptothecin derivative, CPT-11, against human tumor xenografts in nude mice.

The antitumor effects of the camptothecin (CPT) derivative CPT-11, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin , were tested on human tumor xenografts in nude mice. CPT-11 showed antitumor activity higher than that of Adriamycin, 5-fluorouracil, or futraful, with little or no reduction of body weight being observed in the mice. The growth of colon adenocarcinoma Co-4 was significantly inhibited after a single i.v. injection of CPT-11 at 25, 50, or 100 mg/kg. The single i.v. injection was also significantly effective against mammary carcinoma MX-1 and gastric adenocarcinoma St-15. All of the mice bearing MX-1 tumors were cured by the administration of CPT-11 every 4 days for a total of three treatments at a total dose of 200 mg/kg given i.v. or of 400 mg/kg given p.o. Three i.v. or oral treatments were also effective against Co-4, St-15, gastric adenocarcinoma SC-6, and squamous-cell lung carcinoma QG-56. To achieve the same efficacy attained by i.v. injection, however, oral doses 2-4 times higher than the i.v. doses were required. When the total dose was fixed at 100 mg/kg, a triple i.v. injection was most effective, followed by a single i.v. injection and, finally daily p.o. administration for 10 days. Although SN-38 (7-ethyl-10-hydroxycamptothecin), a metabolite of CPT-11, showed much stronger cytotoxic activity in vitro than did CPT-11, its antitumor effects were similar, if not inferior, to those of CPT-11 in vivo at the same dose level. CPT-11 was converted into SN-38 by human tumors, but the sensitivity of these tumors to CPT-11 in vivo was independent of their ability to produce SN-38. These results suggest that CPT-11 may be clinically effective, depending on the schedule of administration, but that its effectiveness is not related to the ability of the tumor to produce SN-38.

Diarylheptanoids suppress expression of leukocyte adhesion molecules on human vascular endothelial cells.

Diarylheptanoids possess potent anti-inflammatory properties. However, the mechanism of their action is not fully understood. In this study, we found that three diarylheptanoids, 1-(3, 5-dimethoxy-4-hydroxyphenyl)-7-phenylhept-1-en-3-one (YPE-01), yakuchinone B and demethyl-yakuchinone B, reduced the adhesion of both human monocytic cell line U937 and human eosinophilic cell line EoL-1 cells to tumor necrosis factor-alpha (TNF-alpha)-treated human umbilical vein endothelial cells. In addition, they suppressed interleukin-1beta- or TNF-alpha-induced expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on the surface of the endothelial cells. Since YPE-01 reduced both VCAM-1 and ICAM-1 mRNA induction in TNF-alpha-stimulated endothelial cells, diarylheptanoids appeared to suppress adhesion molecule expression at the transcriptional level. Furthermore, YPE-01 suppressed both VCAM-1 and ICAM-1 mRNA induction as well as edema in 12-O-tetradecanoylphorbol 13-acetate (TPA)-inflamed mice ears in vivo. These results suggest that the anti-inflammatory action of diarylheptanoids is, at least in part, due to their suppressive effect on the surface expression of inducible adhesion molecules in endothelial cells, and subsequent leukocyte adhesion.