Effect of a newly synthesized leukotriene antagonist, (E)-2,2-diethyl-3'-2-2-(4-isopropyl) thiazolyl ethenyl succinanilic acid (MCI-826), on immunological liver injury and nephritis in mice

The effect of a newly synthesized leukotriene antagonist, (E)-2,2-diethyl-3'-2-2-(4-isopropyl) thiazolyl ethenyl succinanilic acid (MCI-826), on liver injury and nephritis in mice was studied. In order to confirm the anti-leukotriene activity of MCI-826, the effect of MCI-826 on leukotriene C4(LTC4)- and leukotriene D4(LTD4)-induced vasculitis, liver and kidney injury was studied. MCI-826 was found to clearly inhibit LTC4- and LTD4-induced vasculitis, as well as liver and kidney injury. In addition to LT-induced reactions, MCI-826 inhibited liver injury induced by injection of either an anti-basic liver protein antibody into DBA/2 mice that had been previously immunized with rabbit IgG or of a bacterial lipopolysaccharide (LPS) into Corynebacterium parvum pretreated DDY mice. Moreover, MCI-826 inhibited nephritis, caused by injecting antiglomerular basement membrane antibody into C57BL/6 mice. These results suggest that MCI-826 can be applied to the treatment of certain tissue inflammatory diseases.

Participation of collagenase and elastase in LPS-induced airway hyperresponsiveness in guinea pigs

Bacterial lipopolysaccharide (LPS) cause airway hyperreactivity in guinea pigs pretreated with metopirone. LPS inhalation resulted in an increase in airway muscarinic reactivity measured by intravenous acetylcholine injection 1-4 h after the inhalation of LPS. The increase of pulmonary capillary permeability was observed 1-24 h after the inhalation of LPS, whereas the increase of leukocytes in bronchoalveolar lavage fluid (BALF) was observed 2 and 24 h after the inhalation of LPS. Increased cells are mainly neutrophil, eosinophil, and macrophage. From the histopathological study, acute mucosal injury and loss of epithelial cilia were observed 1-24 h after the inhalation of LPS. In order to investigate the phlogistic substance in LPS-induced hyperreactivity, the roles of collagenase and elastase were investigated. The activities of both enzymes were elevated 2 h after the inhalation of LPS. The inhalation of collagenase and elastase caused bronchial hyperreactivity and increased pulmonary permeability. The combined administration of prednisolone (10 mg/kg/day) and cyclophosphamide (10 mg/kg/day) for five days decreased LPS-induced hyperreactivity, pulmonary capillary increase, collagenase and elastase activities, and the number of nucleated cells in BALF 2 h after the inhalation of LPS. These results indicate the participation of collagenase and elastase in the onset of LPS-induced airway hyperreactivity in guinea pigs.

The effects of thromboxane A2 inhibitors (OKY-046 and ONO-3708) and leukotriene inhibitors (AA-861 and LY-171883) on CCl4-induced chronic liver injury in mice

The effects of OKY-046, a selective thromboxane A2 (TxA2) synthetase inhibitor, ONO-3708, a novel TxA2 receptor antagonist, AA-861, a selective 5-lipoxygenase inhibitor and LY-171883, a peptide leukotrienes (p-LTs) receptor antagonist on the chronic liver injury were investigated in mice. The chronic liver injury was induced by the injection of carbon tetrachloride (CCl4) two times a week for twelve weeks in mice. In chronic liver injury models, significant histopathological changes in the liver and extensive elevation of glutamate transaminase (GOT and GPT) activity were observed. Administration of OKY-046, ONO-3708, AA-861 and LY-171883 for 12 weeks suppressed the elevation of serum GOT and GPT levels and histopathological changes in CCl4-induced chronic liver injury. These results suggest that TxA2 and LTs inhibitors are effective for the onset and development of chronic liver injury in mice.

Role of peptide-leukotrienes in liver injury in mice

The role of peptide leukotrienes (p-LTs), especially LTC4 and LTD4 in liver disease, was investigated in mice experimental liver injury models. The liver injury was induced by the injection of bacterial lipopolysaccharide (LPS) into Corynebacterium parvum pretreated mice. Carbon tetrachloride (CCl4)-induced liver injury in mice was used as a standard model. In both injury models, extensive liver parenchymal cell damage was observed by the elevation of glutamate transaminase (GOT and GPT) activity and confirmed by significant histopathological changes in the liver. Moreover, significant elevation of LTC4 in the liver was observed in both models 1 and 6 h after the onset of disease. Administration of AA-861, a selective 5-lipoxygenase inhibitor (0.5, 1, and 2 mg/kg) and LY-171883, a p-LT receptor antagonist (50 and 200 mg/kg) suppressed the elevation of serum GOT and GPT levels and histopathological changes in both experimental liver injury models. In addition, when authentic LTC4 or LTD4 was injected into the mouse, clear elevation of serum GOT and GPT and histopathological changes of the liver were observed. These results suggest that p-LTs play a role in the onset of liver diseases in mice.

The role of thromboxane A2 [TxA2] in liver injury in mice

The role of thromboxane A2 (TxA2) in CCl4-induced liver disease was investigated in mice. Significant elevation of TxB2 in the liver was observed 6 hours after the injection of CCl4. Administration of OKY-046, a selective TxA2 synthetase inhibitor (10 and 50 mg/kg) and ONO-3708, a TxA2 receptor antagonist, (0.5, 1 and 2 mg/Kg) suppressed the elevation of serum GOT and GPT levels and histopathological changes of the liver. In addition, OKY-046 inhibited the elevation of TxB2 in the liver. When U-46619, a stable TxA2 mimetic was injected i.v. into the mice, clear elevation of serum GOT and GPT levels and histopathological score of the liver were observed. These results suggest that TxA2 play a role for the onset of CCl4-induced liver injury in mice.

Effect of OKY-046 and ONO-3708 on liver injury in mice

The effects of OKY-046, a selective thromboxane A2 (TXA2) synthetase inhibitor, and ONO-3708, a novel TXA2 receptor antagonist, on liver disease were investigated in mice. The liver injury was induced by either an injection of antibasic liver protein (BLP) antibody into DBA/2 mice that had been previously immunized with rabbit IgG or by an injection of bacterial lipopolysaccharide (LPS) into Corynebacterium parvum (C. parvum) pretreated DDY mice. 1) In both injury models, clear elevation of glutamate transaminase (GOT and GPT) activity due to extensive liver parenchymal cell damage was observed; this was confirmed by significant histopathological changes in the liver. 2) Typical histopathological changes in the liver were submassive hepatocellular necrosis in the anti-BLP antibody-induced injury model and focal necrosis in the LPS-induced model. Inflammation and increased cell infiltration in portal connective tissue were observed in both cases. 3) Administration of OKY-046 (50 mg/kg) and ONO-3708 (0.5, 1.0 and 2.0 mg/kg) suppressed the elevation of serum GOT and GPT levels and histopathological changes in both experimental liver injury models. 4) Indomethacin inhibited the development of liver disease caused by anti-BLP antibody but not by bacterial LPS. Prostaglandin I2 inhibited the elevation of serum GOT and GPT levels and histopathological changes of the liver in the mice treated with anti-BLP antibody and showed the tendency to inhibit the development of liver injury caused by bacterial LPS.

Anti-allergic action of glucocorticoids (II). Effect of glucocorticoids on cell mediated (type IV) allergic reactions

The effects of three glucocorticoids (steroids; hydrocortisone, prednisolone and dexamethasone) on cell mediated hypersensitivity (type IV) reactions in rats and mice were studied. All the steroids inhibited both the induction and the effector phases of type IV reaction induced by sheep red blood cells (SRBC) in mouse footpads. The local graft vs host reaction induced by lymphocytes from Brown Norway rats into the footpads of (Lewis x Brown Norway) F1 rats was also clearly inhibited by steroids. The inhibitory action of steroids on footpad reactions induced by SRBC was clearly prevented by pretreatment with non-corticoidal steroids (17 alpha-methyltestosterone, androstenedione and progesterone). The release of lymphokines, macrophage chemotactic factor (MCF) and skin reactive factor (SRF) was inhibited by each steroid at a high concentration. Moreover, steroids inhibited the activity of MCF in vitro and SRF in vivo.

Liver injury model in mice for immunopharmacological study

Experimental liver injury was produced in mice by the immunological technique. The utility of these models as an immunopharmacological method was investigated. The first model was produced by the injection of anti-basic liver protein (BLP) rabbit antibody into DBA/2 mice that had been previously immunized with rabbit IgG. The second liver injury was caused by injection of anti-liver specific protein (LSP) rabbit antibody into DBA/2 mice. The third model was produced by the injection of bacterial lipopolysaccharide (LPS) into Corynebacterium parvum pretreated ddY mice. In all injury models, extensive liver parenchymal cell damage was estimated by elevation of glutamate transaminase (GOT and GPT) activity. These were confirmed by histopathological studies of the liver. Typical histopathological changes in the liver from injured mice were submassive hepatocellular necrosis and infiltration of granulocytes and lymphocytes into the portal tract and sinusoid in the necrotic lesion. Administration of prednisolone and cyclophosphamide for 10 days prior to injection of eliciting antibodies or LPS suppressed the elevation of serum transaminase levels in all experimental liver injury models. Cianidanol and sylibin inhibited the elevation of GOT and GPT in anti-BLP induced liver injured mice. These evidences suggest that the above models are suitable for investigating the remedy for liver diseases.

The effect of 6-amidino-2-naphtyl-4-guanidinobenzoate dimethane sulfonate (FUT-175) on experimental glomerulonephritis in mice

Effect of 6-amidino-2-naphtyl-4-guanidinobenzoate dimethane sulfonate (FUT-175) on experimental glomerulonephritis in mice was studied. Employed models are nephrotoxic serum (NTS) nephritis in ddY or A/He mice, rabbit IgG (RGG) accelerated NTS nephritis in ddY mice and spontaneous nephritis in (NZB x NZW) F1 mice. The severity of nephritis was evaluated by measuring proteinuria and serological parameters and examining renal tissue by light microscopy. Therapy with FUT-175 clearly prevented the pathological changes of proteinuria and serological parameters in all four nephritis models. By contrast, treatment hardly affected histopathological changes of the kidney in any of the models. Cyclophosphamide used as a comparative drug showed more clearly remission of the onset and development of NTS nephritis and RGG accelerated NTS nephritis in ddY mice by means of the changes of urinary and selorogical parameters. These evidences suggest that FUT-175 shows beneficial effects on the nephritis in either normal or complement deficient mice.

Immunopharmacological studies on experimental glomerulonephritis

Immunopharmacological studies on modified nephrotoxic serum (NTS) nephritis in rats were conducted. The modified NTS nephritis was produced by an intravenous (i.v.) injection of NTS in a subnephrotoxic dose (sub-dose) into the rats which had been previously immunized with rabbit IgG (RGG) and complete Freund's adjuvant (CFA). In previously immunized rats, typical nephritic syndrome was demonstrated with respect to the elevation of urinary protein, serum cholesterol, blood urea nitrogen (BUN) and histopathologic scores of the kidneys. No changes in complement levels were found. By adoptive transfer experiments, it was found that sensitized lymphocytes were essential for causing the nephritis. The potency of the sensitized lymphocytes was reinforced by passing them through a nylon wool or Sephadex G-10 column after treatment with rabbit anti-rat F(ab')2 antibody and complement. The administration of cyclophosphamide, prednisolone, tilorone or cis-1-methyl-4-isohexylcyclohexane carboxylic acid (IG-10) showed a clear remission of nephritis. Cobra venom factor (CoVF) and Cu-chlorophyllin complement inhibitors showed a contradictory efficacy on the nephritis. CoVF which decreased the serum CH50 value did not produce any remission of the nephritis, whereas Cu-chlorophyllin, which slightly decreased CH50 values produced a significant decrease in urinary protein and serum cholesterol. The macrophage-toxic agents carrageenan and dextran sulfate, also did not produce a remission of nephritis. These findings suggest that the participation of T cells is important for the onset of this nephritis and that macrophages and complement do not appear to be involved.

Immunopharmacological studies of the aqueous extract of Cinnamomum cassia (CCAq). I. Anti-allergic action

Effect of the aqueous extract of Cinnamomum Cassia (CCAq) on experimental allergic reaction was investigated. IgE mediated reactions, homologous passive cutaneous anaphylaxis (PCA), degranulation of mast cells, and the release of histamine from sensitized lung tissues classified as the type I reaction by Coombs and Gell were not affected by CCAq. Complement dependent reactions including reversed cutaneous anaphylaxis (RCA), Forssman cutaneous vasculitis (FCV), and nephrotoxic serum (NTS) nephritis classified as type II and the Arthus reaction classified as type III were clearly inhibited by CCAq. However, CCAq did not affect the nephritis caused by the F(ab')2 portion of the nephrotoxic IgG antibody. CCAq in a high concentration inhibited the immunological hemolysis, chemotactic migration of neutrophils in response to complement activated serum, and the generation of chemotactic factors. The type IV reaction, contact dermatitis, was not affected by CCAq. The production of hemolytic plaque forming cells was slightly inhibited by CCAq. These results suggest that CCAq has an anticomplement action and inhibits the complement dependent allergic reaction.

Immunopharmacological studies of the aqueous extract of Cinnamomum cassia (CCAq). II. Effect of CCAq on experimental glomerulonephritis

Effect of the aqueous extract of Cinnamomum Cassia (CCAq) on experimental glomerulonephritis was studied and compared with that of cobra venom factor (CoVF). In rat nephrotoxic serum (NTS) nephritis, CCAq clearly inhibited the excretion of protein into the urine and the increase of peripheral leucocyte counts. The histological score in CCAq administered animals was significantly lower than that in control animals. However, CCAq did not inhibit or lower the serum complement level. Contrary to CCAq, hypocomplementation was observed by the administration of CoVF, and the excretion of protein into urine was inhibited in a high dose group. In immune complex (IC) and autologous IC nephritis in rats, CCAq clearly inhibited the excretion of protein into urine and the elevation of blood urea nitrogen (BUN). The administration of CoVF caused hypocomplementation, but little inhibition of the excretion of urinary protein was observed in both types of immune complex nephritis. The histological score was slightly inhibited by a low dose of CCAq and a high dose of CoVF. In the experiment employing NZB/NZW F1 mice, the proteinurea, the elevation of BUN level, and the production of antibodies were clearly inhibited by the administration of CCAq. Similar inhibition was observed by CoVF at a high dose. However, the histological changes of the kidney in NZB/NZW F1 mice were not prevented by the administration of CCAq or CoVF.