Pharmacological studies of FUT-175, nafamstat mesilate. III. Anti-inflammatory activities of FUT-175

Anti-inflammatory effects of FUT-175 (nafamstat mesilate), a new synthetic serine protease inhibitor, on various types of experimental inflammation were investigated in vivo and in vitro, in comparison with non-steroidal anti-inflammatory drugs (NSAID). The in vivo studies showed that FUT-175 has the abilities to inhibit almost all types of inflammatory reactions employed in the present study. In particular, being evaluated on the basis of the effect of indomethacin, FUT-175 exhibited relatively higher potencies against some reactions such as zymosan-induced increase of vascular permeability, scald paw edema, zymosan-induced granuloma-pouch, the Arthus reaction and acetic acid-induced writhing in which the complement system or the kallikrein-kinin system are considered to play an important role. The in vitro studies showed that FUT-175 is quite different from NSAID, that is, FUT-175 had no effects on heat-induced erythrocyte-lysis and heat-induced denaturation of bovine serum albumin. FUT-175 also had no effect on chemotaxis of polymorphonuclear leucocytes, but inhibited the production of chemotactic factor by antigen-antibody reaction. These above results suggested that FUT-175 has a different mode of action from NSAID and that serine protease inhibiting activities of this compound might play an important role in its anti-inflammatory effect.     

The effects of FUT-175 (nafamostat mesilate) on blood coagulation and experimental disseminated intravascular coagulation (DIC)

FUT-175 is a newly synthesized serine protease inhibitor. In the present study, we investigated the effects of FUT-175 on blood coagulation and experimental DIC. The effects on coagulation were examined in vitro by measuring the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) of rat plasma in the presence of FUT-175. FUT-175 exhibited remarkable anticoagulative effects to prolong APTT at a plasma concentration of 3 x 10(-7) M, PT at 1 x 10(-5) M and TT at 3 x 10(-5) M. The anticoagulative effect of FUT-175 at 1 x 10(-6) M on APTT was almost similar to that of heparin at 0.3 U/ml or that of gabexate mesilate at 1 x 10(-3) M. Experimental DIC was induced by a four-hr sustained intravenous infusion of endotoxin. FUT-175 was administered intraperitoneally prior to the injection of endotoxin or infused intravenously with endotoxin. As a result, the prolongation of APTT and PT, the decreases of fibrinogen level, platelet counts and complement level, and the increase of FDP were remarkably improved by FUT-175. Furthermore, glomerular fibrin deposits were reduced by the infusion of FUT-175. These results indicate that FUT-175, having a potent inhibitory effect on blood coagulation, is clinically applicable to therapy for DIC.     

Inhibitory effect of nafamostat mesilate (FUT-175) on O2- production in rat polymorphonuclear leucocytes

Effect of nafamostat mesilate (FUT-175), a serine protease inhibitor, having anti-inflammatory effects was studied on superoxide (O2-) production in rat polymorphonuclear leucocytes (PMN) and compared with those of other serine protease inhibitors and typical anti-inflammatory agents. 1) O2- productions in rat PMN stimulated with concanavalin A (Con A) and cytochalasin B (Cyt B) were too weak to observe. With NADH, however, strong O2- production was induced by Con A and Cyt B. 2) FUT-175 at 10(-6) and 10(-5) M inhibited O2- production in rat PMN induced by Con A and Cyt B with NADH in a concentration-dependent manner. 3) The serine protease inhibitor L-tosylamido-2-phenylethyl-chloromethyl ketone (TPCK) and soybean trypsin inhibitor (SBTI) inhibited O2- production at 10(-5) M and 10(-4) M, respectively, while aprotinin, chymostatin and leupeptin did not. 4) Neither indomethacin nor dexamethasone, typical anti-inflammatory agents, inhibited O2- production. Mepacrine, a phospholipase A2 inhibitor, strongly inhibited it. 5) O2- production in PMN prepared from the rat administered FUT-175, 200 mg/kg, p.o., was significantly decreased in comparison with that of the control rat. 6) FUT-175 had no effect on O2- production by hypoxanthine-xanthine oxidase. These results showed FUT-175 had a strong inhibitory effect on O2- production in rat PMN which other typical anti-inflammatory agents did not have.     

乌司他丁对实验性急性胰腺炎胰腺组织病理学变化的影响

目的观察在牛磺胆酸钠溶液逆行胆胰管注射诱发的大鼠急性胰腺炎模型中,乌司他丁的应用对胰腺组织病理学改变的影响,探讨胰酶抑制在急性胰腺炎治疗中的作用和急性胰腺炎发生和加重的机制。方法雄性SD大鼠72只,随机分成4大组。分别是EP组（3%牛磺胆酸钠逆行胆胰管注射组）;TP组（3%牛磺胆酸钠逆行胆胰管注射后30min经股静脉注入乌司他丁组）;CP组（0.9%氯化钠注射液逆行胆胰管注射组）;OP组（假手术组,只行开关腹术）。每大组18只动物,每大组再随机分成A、B、C三组,每组6只动物,分别于制模后3、6、24h后取血处死,留取标本。观测指标有血清淀粉酶、血清IL-6水平并在光镜下对胰腺病变进行双盲的组织病理学评分。结果 EP组和TP组动物随制模时间的增加,胰腺病理组织学评分亦增高。TP组与EP组相比,制模后24h,胰腺病理损害差异非常显著。制模后6h,24h血清IL-6水平TP组（489.81±33.88）pg/ml和（652.22±40.39pg/ml）明显低于EP组（619.07±42.25）pg/ml和（903.35±48.44）pg/ml（P〈0.01）。结论在此牛磺胆酸钠逆行胆胰管注射诱发的大鼠AP模型中,乌司他丁的应用对于大鼠胰腺组织病理学的发展有非常显著的抑制作用,同时还能够有效抑制血液中炎性介质的产生,从而对于急性胰腺炎的病程产生干预。乌司他丁有望在临床急性胰腺炎患者的治疗中发挥更加积极的作用。     

Comparative studies of nafamostat mesilate and various serine protease inhibitors in vitro

Inhibitory effects of nafamostat mesilate (nafamostat) on various enzymes were investigated, and they were compared with those of gabexate mesilate (gabexate), leupeptin, aprotinin and urinastatin in vitro. Nafamostat inhibited trypsin, plasmin, thrombin, pancreatic kallikrein, Clr and Cls more potently than gabexate and leupeptin. Gabexate and leupeptin did not inhibit pancreatic kallikrein and thrombin, respectively. Aprotinin inhibited trypsin, plasmin, pancreatic kallikrein and chymotrypsin. Urinastatin inhibited trypsin and chymotrypsin. Nafamostat inhibited the complement-mediated hemolysis in diluted serum more potently than gabexate and leupeptin, but aprotinin and urinastatin did not. Nafamostat, furthermore, inhibited the complement-mediated hemolysis in undiluted serum, but gabexate did not. Unlike aprotinin and urinastatin, nafamostat and gabexate inhibited alpha 2-macroglobulin bound trypsin as well as free trypsin to the same extent. The inhibitory effect of gabexate toward trypsin was reduced more markedly than that of nafamostat after incubation with plasma at 37 degrees C. These results show that nafamostat is more useful than other inhibitors such as gabexate, leupeptin, aprotinin and urinastatin.     

Oral administration of sepimostat mesilate prevents acute alcohol pancreatic injury in rats.

The preventive effect of a novel synthetic serine protease inhibitor, sepimostat mesilate (sepimostat), on acute alcohol pancreatic injury, induced by exocrine hyperstimulation and ethanol administration, was assessed and compared with that of a similar protease inhibitor, camostat mesilate (camostat). Conscious rats were infused with 1 microg mL(-1) h(-1) caerulein intravenously for 6 h and with 0.1 g mL(-1) h(-1) ethanol for 9 h, with the latter infusion beginning 3 h after the start of the caerulein infusion. Sepimostat or camostat was administered orally 1 h before the caerulein infusion. Rats infused with caerulein plus ethanol showed increased plasma amylase and lipase activities, and aggravated pancreatic interstitial oedema when compared with rats given caerulein alone. Sepimostat at 10 and 30 mg kg(-1) prevented the increase in plasma amylase and lipase activities caused by caerulein plus ethanol infusion. Sepimostat at 30 mg kg(-1) suppressed the histological change. Camostat did not show any preventive effects at the equivalent dose. When conscious rats were infused with 1 microg mL(-1) h(-1) caerulein alone intravenously for 6 h, plasma amylase and lipase activities were increased compared with rats given saline. Neither drug prevented the increase in these activities at 30mg kg(-1). Our results suggest that sepimostat has superior preventive effects on alcohol-induced acute pancreatic injury compared with camostat. Sepimostat may thus be a useful drug in the therapy of alcohol-induced pancreatitis.     

Pharmacological efficacy of delta sleep-inducing peptide in experimental acute pancreatitis

The development of experimental acute pancreatitis (EOP) in rats is accompanied by (i) intensification of the lipid peroxidation (LPO) process and the accumulation of malonic dialdehyde (MDA, an LPO product) in the tissues of pancreas, liver, and kidney and in the blood serum, (ii) destabilization of membranes and reduction of the osmotic resistance of erythrocytes (ORE), (iii) increase in the concentration of extracorpuscular hemoglobin (ECH) and medium-molecular-weight molecules (MWM) in the blood serum, and intensification of protein autolysis in tissues. Preliminary triple intraperitoneal administration of a delta-sleep-inducing peptide (DSIP) in a dose of 12 micrograms/100 g body weight to the test rats with EOP stabilized LPO, improved the erythrocyte membrane structure, reduced the MDA level in tissues and blood serum, increased ORE, reduced the ECH and MWM level in the blood, and decreased the protein autolysis rate in tissues.     

Immunopharmacological actions of 6-amidino-2-naphthyl-4-guanidinobenzoate (FUT-175). 2. Effect of FUT-175 on immunological reactions in man

FUT-175 is a new anti-complemental drug which strongly inhibits complement-mediated allergic reactions in animals. It was reported that FUT-175 does not affect both antibody formation and host defense to bacterial infection in mice. The present study was undertaken to examine the effects of FUT-175 on various immunological reactions in humans. FUT-175 dose-dependently decreased the antigen-induced anaphylactic histamine release from leukocytes of atopic patients. However, i.d. treatment of FUT-175 neither inhibited antigen- or compound 48/80-induced immediate type skin reactions in atopic patients nor antigen-induced early, late or delayed type skin reactions in Candida-sensitive patients. FUT-175 also did not inhibit the PPD-mediated delayed type skin reaction in healthy subjects. FUT-175 at a dose of 10(-4)M but not at 10(-8) to 10(-5)M significantly decreased the proliferation of human atopic peripheral blood lymphocytes (PBL) caused by mite antigen, concanavalin A or pokeweed mitogen. 51Cr release from human PBL was slightly enhanced by FUT-175 at a dose range of 10(-6) to 10(-4)M. FUT-175 did not change the number of SIg receptors or C3 receptors on human B cells. FUT-175 hardly affected the nitroblue tetrazolium reduction test and Escherichia coli-mediated chemotaxis in human neutrophils. These results strongly suggest that FUT-175 does not affect immunological functions and host defense in humans.     

Effects of the bradykinin antagonist, HOE 140, in experimental acute pancreatitis.

1. The novel bradykinin antagonist, HOE 140, completely blocked the fall in rabbit blood pressure caused, not only by i.v. bradykinin, but also by i.v. kallikrein. This shows that both the effects of exogenously administered bradykinin and those of endogenously released kinins are antagonized by HOE 140. 2. Acute pancreatitis was induced in rats by i.v. infusion of the cholecystokinin analogue, caerulein. This treatment resulted in massive oedema of the pancreas, increased activities of amylase and lipase in serum and a characteristic, biphasic fall in blood pressure. 3. HOE 140 prevented the caerulein-induced pancreatic oedema and the second phase of hypotension whereas NPC 349, a widely used, but short-acting, bradykinin antagonist did not show a significant inhibition. HOE 140, in contrast to its inhibitory effects on caerulein-induced pancreatic oedema and hypotension, significantly augmented the increases in amylase and lipase activities in serum. 4. It is concluded that in this model of acute pancreatitis, the release of kinins induces pancreatic oedema and hypotension. Prevention by HOE 140 of the kinin-induced oedema allows the pancreatic enzymes to leave the tissue without hindrance and thus will diminish subsequent pathological events. It is suggested that the results obtained with the highly potent and long-acting bradykinin antagonist, HOE 140, provide a pharmacological basis for a clinical trial in acute pancreatitis.     

Effects of FUT-175, a novel synthetic protease inhibitor, on the development of adjuvant arthritis in rats and some biological reactions dependent on complement activation

1. The effects of FUT-175 on the development of adjuvant arthritis in rats were studied and compared with those of indomethacin. FUT-175 inhibited both primary and secondary paw lesions in the adjuvant arthritic rats when it was administered orally on a daily basis from the day before through 18th day after adjuvant injection. 2. In addition, FUT-175 inhibited the increase in hemolytic complement in adjuvant arthritic rats in a dose-dependent manner. 3. Indomethacin also showed an inhibitory effect on the development of arthritic lesion, but had no effect on the increase in hemolytic complement in the adjuvant arthritis in rats. 4. Furthermore, FUT-175 inhibited the activities of various proteases in vitro, and then strongly inhibited complement-mediated hemolysis via the classical and alternative pathways, while indomethacin had no effect on them. 5. These results suggest that the anti-inflammatory activity of FUT-175 may differ from indomethacin in the mechanisms of action and, at least in part, due to the anti-complement activity.     

Meta-analysis of somatostatin, octreotide and gabexate mesilate in the therapy of acute pancreatitis

Background:

Autodigestion of the pancreas, secondary to the activation of digestive enzymes, is the pathogenetic mechanism of acute pancreatitis (AP).

Aim:

Clinical trials in which somatostatin (SS), octreotide (OCT) and gabexate mesilate (FOY) were used to treat patients with AP, were submitted to a meta-analytical evaluation. Five end-points were evaluated: early and overall mortality, patients with complications, complication rate, and patients who needed surgery.

Results:

In mild AP, no agent proved of value. In severe AP, both SS and OCT were beneficial in improving the overall mortality: the odds ratios (OR) were, respectively, 0.36 (95% CI: 0.20–0.64, P = 0.001) and 0.57 (95% CI: 0.35–0.88, P = 0.006). FOY had no effect on either early or overall mortality, but was effective in improving complication rate (OR = 0.70, 95% CI: 0.56–0.88, P = 0.02), number of patients with complications (OR = 0.61, 95% CI: 0.41–0.91, P = 0.01), and number of cases submitted to surgery (OR = 0.60, 95% CI: 0.39–0.92, P = 0.01). SS and OCT had no effect on these latter outcomes.

Conclusions:

Antisecretory agents, such as SS and OCT, are able to reduce mortality without affecting complications, whereas antiproteases, such as FOY, have no effect on mortality but do reduce complications. A trial exploring the efficacy of combining antisecretory agents with antiproteases would be of great benefit in patients with severe AP.

     

Immunopharmacological actions of 6-amidino-2-naphthyl-4-guanidinobenzoate (FUT-175). 1. Effect of FUT-175 on immune response and host defense in mice

FUT-175 is a new synthetic protease inhibitor which strongly inhibits complement-mediated hemolysis via the classical and alternative pathways. The present study was undertaken to examine the effects of FUT-175 on antibody formation and host defense in mice since the complement system participates in both immunological responses and host defense against bacterial infection. FUT-175 did not suppress the primary IgM and IgG antibody responses to sheep red blood cells, although FUT-175 was given at 10 to 100 mg/kg/day p.o. for 3 days before or after immunization. On the other hand, the primary anti-DNP IgE antibody response to DNP-conjugated ovalbumin was slightly suppressed only by post-administration of FUT-175 in a dose of 100 mg/kg/day p.o. for 5 days. However, the results of the adoptive transfer experiments indicate that FUT-175 did not affect either T cells or B cells participating in the secondary anti-DNP IgE antibody formation. FUT-175 in a dose of 10(-4)M but not at 10(-6) to 10(-5)M significantly decreased the proliferation of spleen cells caused by concanavalin A, lipopolysaccharide or the one-way mixed lymphocytes culture reaction using 1000 R-irradiated spleen cells from BDF1 mice as stimulator cells and those from C57BL/6 mice as responder cells. FUT-175 had an inhibitory rather than an enhancing effect on host defense to infection with Escherichia coli when administered at 10 to 100 mg/kg/day p.o. for 3 days before or after infection. These results strongly suggest that FUT-175 does not affect antibody formation and host defense in mice.     

Effects of direct haemoperfusion through fibres immobilizing polymyxin B and nafamostat mesilate on endotoxaemia in conscious Guinea-pigs

1. Direct haemoperfusion through a network of fibres immobilizing polymyxin B (PMX-B) is used for the treatment of septic shock, but the mechanism underlying its clinical benefits remains unclear. The aims of the present study were to assess the actions of direct haemoperfusion through fibres immobilizing PMX-B (PMX-DHP) on the effects of exogenously administered endotoxin in conscious guinea-pigs and to examine the difference in the effects of heparin compared with nafamostat mesilate (NM) used as an anticoagulant. Although nafamostat is widely used in Japan, the agent cannot necessarily be used elsewhere in the world. Therefore, the study aimed to investigate and elucidate the effectiveness of NM compared with heparin. 2. Colonic motion was monitored continuously via telemetry using a force transducer attached to the taenia caecum, whereas blood pressure was monitored using a carotid artery catheter. To establish a haemoperfusion circuit in each freely moving and conscious guinea-pig, catheters were implanted in the carotid artery and the jugular vein, tunnelled subcutaneously, exteriorized at the back of the neck in contact with a lightweight tethering spring and attached to a swivel device at the top of the cage. On the day after the operation, lipopolysaccharide (LPS; Escherichia coli, O111:B4; 1 mg/kg) was administered i.v. and PMX-DHP was conducted for 2 h. Heparin (50 IU/h) or NM (0.4 mg/h) was used as the anticoagulant. Furthermore, guinea-pigs were administered a lethal dose of LPS (10 mg/kg) and the survival rate was examined for animals undergoing PMX-DHP compared with control animals. 3. In guinea-pigs treated with PMX-DHP, relaxation of colonic longitudinal muscle caused by LPS was significantly suppressed, as were decreases in blood pressure. Of the two anticoagulants used, NM was more effective than heparin. In addition, PMX-DHP significantly increased the survival rate of guinea-pigs that received potentially lethal doses of LPS. 4. In conscious and unrestrained guinea-pig endotoxaemia model, PMX-DHP significantly improved intestinal paralysis and decreases in blood pressure. These effects were augmented more by NM than by heparin when an anticoagulant was used in the perfusion process. These findings suggest that haemoperfusion using PMX and NM performed in the early stage of endotoxaemia is an effective treatment.     

乌司他丁治疗急性胰腺炎的临床疗效分析

目的对比乌司他丁和加贝酯对急性胰腺炎的疗效。方法回顾性对比分析2000年6月~2005年6月共103例急性胰腺炎,应用乌司他丁、加贝酯和其他方法的治疗效果。结果乌司他丁治疗组体温、SpO2、腹部胀痛及压痛减轻程度与加贝酯组和对照组差异有显著性(P<0.05),血压、心率、呼吸、肠鸣音恢复显著优于对照组(P<0.05)。结论乌司他丁早期应用能在短时间内控制急性胰腺炎的恶化,减少并发症发生率。     

Pharmacological studies on schizandra fruits. III. Effects of wuweizisu C, a lignan component of schizandra fruits, on experimental liver injuries in rats

The effects of wuweizisu C, a lignan component of schizandra fruits, on liver injuries induced by carbon tetrachloride (CCl4), d-galactosamine and dl-ethionine were investigated by means of serum-biochemical and histopathological examinations in rats. Pretreatment or combined administration of wuweizisu C dose-dependently reduced the elevation of serum transaminase activity and histological changes such as fatty degeneration, cell necrosis, inflammatory cell infiltration, etc., which were caused by the single administration of 1 ml/kg, p.o., or the repeated administration of 0.2 ml/kg, s.c., daily for 4 days of CCl4, respectively. The effects of wuweizisu C on the liver injuries induced by a low dose (200 mg/kg, i.p.) and a high dose (400 mg/kg, i.p.) of d-galactosamine were compared with those of uridine. Wuweizisu C significantly lowered the rise of serum transaminase activity after the administration of a low dose of d-galactosamine in the serum-biochemical analysis. A tendency was also shown to inhibit cell necrosis and inflammatory cell infiltration caused by both doses of d-galactosamine in the histopathological examination. On the other hand, uridine markedly repaired the serum-biochemical and histopathological changes after the administrations of both doses of d-galactosamine. Also wuweizisu C cured the liver injury by the repeated administration of 150 mg/kg, i.p., daily for 4 days of d-galactosamine. After the repeated administration of 250 mg/kg, s.c., daily for 4 days of ethionine, liver cell atrophy, diffuse fatty degeneration and decrease of serum triglyceride were observed, but not cell necrosis. Wuweizisu C dose-dependently inhibited fatty degeneration and decrease of serum triglyceride. These findings suggest that wuweizisu C can be protective and/or therapeutic on hepatocellular phenomena such as cell necrosis, fatty degeneration, inflammatory cell infiltration, etc., in human hepatitis.     

Inhibitory effects of a novel synthetic protease inhibitor, FUT-175, on the paw edema in rats and zymosan-induced complement activation in vitro

FUT-175 inhibited the zymosan-induced rat paw edema in a dose-dependent manner, while indomethacin exhibited no significant activities in this model. FUT-175 also inhibited the decrease in hemolytic complement (CH50) induced by zymosan in vitro, and indomethacin was inactive. These results suggest that FUT-175 has potent in vitro and in vivo inhibitory activity against the activation of the complement system induced by zymosan.     

Cholecystokinin fails to promote pancreatic regeneration in diabetic rats following the induction of experimental pancreatitis.

The aim of the present study was to investigate the spontaneous and cholecystokinin-octapeptide (CCK-8)-promoted laboratory changes and morphological alterations in rats with arginine (Arg)-induced pancreatitis in which diabetes had been induced with streptozotocin (STZ). Male Wistar rats were used in our experiments. Pancreatitis was induced by arginine, diabetes by STZ and regeneration was promoted by CCK-8. The serum amylase, glucose and insulin levels, the pancreatic contents of protein, DNA, amylase, trypsinogen and lipase, the pancreatic weight/body- weight ratio (pw/bw) and the plasma glucagon level were examined 1, 3, 7, 14 and 28 days after pancreatitis induction. Pancreatic tissue samples were examined by light microscopy and immunostaining on paraffin-embedded sections. The insulin and glucagon-containing cells were visualized by using monoclonal antibodies. The administration of low doses of CCK-8 accelerated the processes of regeneration following Arg-induced pancreatitis, but in rats that were also diabetic, pancreatic regeneration was not observed. The administration of low doses of CCK-8 seems to reduce the pancreatic beta -cell number and function in diabetic rats. The pancreatic endocrine function was further deteriorated by simultaneous Arg-induced pancreatitis. The diabetic state appeared to shift the normal pancreatic enzyme content (decreased amylase and increased trypsinogen) in this study.     

大鼠急性胰腺炎胰腺腺泡细胞凋亡研究

目的：探讨急性胰腺炎严重程度与胰腺腺泡细胞凋亡的关系。方法：牛磺胆酸钠逆行胰胆管注射制作不同程度的AP模型，原位末端标记法（TUNEL）检测大鼠胰腺腺泡细胞凋亡率。结果：对照组凋亡细胞很少，AEP组存在较多的细胞凋亡，ANP组凋亡指数较低，两组之间差别有显著性。结论：胰腺腺泡细胞凋亡与急性胰腺炎严重程度呈负相关。