Radiofrequency ablation of hyperplasia at an uncovered portion of a partially covered metal stent in endoscopic ultrasound-guided hepaticogastrostomy (with video).

Highlight Endoscopic ultrasound-guided hepaticogastrostomy with a partially covered metal stent has a potential risk of stent occlusion due to hyperplasia at an uncovered portion of the stent. Matsubara and colleagues report that radiofrequency ablation of hyperplasia with additional placement of an uncovered metal stent is useful for preventing recurrent stent occlusion.

Combination treatment with fingolimod and a pathogenic antigen prevents relapse of glucose-6-phosphate isomerase peptide-induced arthritis.

INTRODUCTION: Combination treatment with fingolimod (FTY720) plus pathogenic antigen is thought to prevent glucose-6-phosphate isomerase (GPI)325-339-induced arthritis progression by effective induction of immune tolerance. Here, we examined the efficacy of this combination treatment on remission maintenance. METHODS: GPI325-339-induced arthritis mice were treated for 5 days with FTY720 (1.0 mg/kg, p.o.) alone, GPI325-339 (10 µg/mouse, i.v.) alone, or with the FTY720 plus GPI325-339 combination. In some experiments, mice were resensitized with GPI325-339. RESULTS: Following resensitization with GPI325-339, combination-treated mice exhibited neither severe relapse nor elevated lymphocyte infiltration in joints. Neither anti-human nor mouse GPI325-339 antibody levels were correlated with clinical symptoms. This suggests that combination treatment prevents relapse following resensitization via regulation of pathogenic antigen-specific T cells. The proportion of regulatory T (Treg) cells in inguinal lymph nodes was increased post treatment in the FTY720 alone and FTY720 plus GPI325-339 groups. In contrast, the proportion of glucocorticoid-induced tumor necrosis factor receptor-family-related gene/protein (GITR)(+) non-Treg cells was increased only in combination-treated mice. Furthermore, GITR(+) non-Treg cells, which were induced by the combination treatment in vivo, possess suppressive activity and high ability to produce interleukin (IL)-10. CONCLUSION: GITR(+) non-Treg cells might play a key role in relapse prevention following resensitization. Thus, this combination treatment might establish immune tolerance by induction of GITR(+) non-Treg cells.

Therapeutic approach to mite-induced intractable dermatitis using novel immunomodulator FTY720 ointment (fingolimod) in NC/Nga mice.

BACKGROUND: The increasing incidence and prevalence of atopic dermatitis (AD) demands new therapeutic approaches for treating the disease. We investigated the therapeutic efficacy of immunomodulator FTY720 ointment (fingolimod) for mite-induced intractable AD using an NC/Nga mouse model. METHODS: Female NC/Nga mice that developed severe AD were divided into four groups: (1) FTY720 (0.001% FTY720 ointment), (2) tacrolimus (tacrolimus hydrate ointment) (3) betamethasone (betamethasone ointment), and (4) ointment base (hydrophilic petrolatum), all of which received treatment six times per week. Therapeutic efficacy after two weeks was evaluated in terms of AD severity, histochemical observations (epidermal hypertrophy, mast cell accumulation, and CD3(+) T cell infiltration), transepidermal water loss (TEWL), and epidermal barrier function (filaggrin expression). RESULTS: Betamethasone treatment showed little effect, confirming that the AD was intractable. In the FTY720 group, AD improved significantly compared with the ointment base group, as did epidermal hypertrophy, mast cell accumulation, and CD3(+) T cell infiltration. In contrast, AD in the tacrolimus and betamethasone groups did not improve significantly, nor did epidermal hypertrophy or mast cell accumulation. Furthermore, in the FTY720 group, TEWL decreased significantly compared with the ointment base group, and filaggrin expression significantly increased compared with the betamethasone and ointment base groups. CONCLUSIONS: FTY720 ointment is a promising candidate for treatment of intractable AD. These findings also provide the first evidence that FTY720 ointment ameliorates epidermal barrier function.

Functional Mechanism(s) of the Inhibition of Disease Progression by Combination Treatment with Fingolimod Plus Pathogenic Antigen in a Glucose-6-phosphate Isomerase Peptide-Induced Arthritis Mouse Model.

We previously reported that combination treatment with fingolimod (FTY720) plus antigenic peptide of glucose-6-phosphate isomerase (residues 325-339) (GPI325-339) from the onset of symptoms significantly inhibited disease progression in a mouse model of GPI325-339-induced arthritis. In this study, we investigated the mechanism(s) involved. The model mice were treated from arthritis onset with FTY720 alone, GPI325-339 alone, or the combination of FTY720 plus GPI325-339. At the end of treatment, inguinal lymph nodes (LNs) were excised and examined histologically and in flow cytometry. Levels of apoptotic cells, programmed death-1-expressing CD4(+)forkhead box P3(-) nonregulatory T cells (non-Tregs), and cytotoxic T-lymphocyte antigen 4-expressing non-Tregs in inguinal LNs were markedly increased in the combination treatment group mice. Regulatory T cells (Tregs) were also increased. These results indicate that combination treatment with FTY720 plus GPI325-339 inhibits the progression of arthritis by inducing clonal deletion and anergy of pathogenic T cells and also by immune suppression via Tregs.

Efficacy of combination treatment with fingolimod (FTY720) plus pathogenic autoantigen in a glucose-6-phosphate isomerase peptide (GPI325-339)-induced arthritis mouse model.

Fingolimod (FTY720) is known to have a significant therapeutic effect in various autoimmune disease models. Here, we examined FTY720 in a model of rheumatoid arthritis, induced by immunizing DBA/1 mice with a peptide consisting of residues 325 through 339 of glucose-6-phosphate isomerase (GPI325-339). The efficacy was evaluated in terms of macroscopic findings, inflammatory cell infiltration and autoantibody level. Prophylactic administration of FTY720 from the day of immunization significantly suppressed the development of paw swelling, but therapeutic administration of FTY720 from onset of symptoms on day 8-9 was less effective. Interestingly, however, combination treatment with FTY720 plus GPI325-339 for 5 d after onset of symptoms significantly reduced the severity of symptoms in all mice, and no relapse occurred after booster immunization. Taking into account the reported mechanism of action of FTY720, these results indicate that combination treatment with FTY720 plus pathogenic autoantigen might efficiently induce immune tolerance by sequestering circulating autoantigen-specific lymphocytes from blood and peripheral tissues to the secondary lymphoid tissues. Combination treatment with FTY720 plus pathogenic autoantigen may become a breakthrough treatment for remission-induction in patients with autoimmune diseases including rheumatoid arthritis.

[Therapeutic approach to mite-induced intractable dermatitis using novel immunomodulator FTY720 (fingolimod) in combination with betamethasone ointment in NC/Nga mice].

BACKGROUND: The increasing incidence and prevalence of atopic dermatitis (AD) have led to a requirement for new means to treat the disease. We investigated the therapeutic efficacy of the novel immunomodulator FTY720 (Fingolimod), alone and in combination with betamethasone valerate ointment, in the NC/Nga mouse model of mite-induced intractable dermatitis. METHODS: Female NC/Nga mice in which dermatitis had been induced with Dermatophagoides farinae were divided into six groups: 1) a betamethasone group (betamethasone ointment, six times a week), 2) an FTY720 group (FTY720, orally, three times a week), 3) an FTY720 plus betamethasone ointment group, 4) an ointment base group (ointment base, six times a week), 5) an FTY720 plus ointment base group and 6) a placebo group (vehicle alone). The therapeutic efficacy was evaluated in terms of the severity of dermatitis and histochemical observations after two weeks of treatment. RESULTS: Betamethasone treatment had little effect, confirming that the dermatitis was intractable. In the FTY720 plus betamethasone ointment group, the dermatitis was significantly improved as compared with the betamethasone ointment and placebo groups. This combination therapy also suppressed epidermal hypertrophy and accumulation of mast cells and CD3+T-cells in dermis, all of which were observed in mice in which the dermatitis had become established. CONCLUSION: Our results strongly suggest that the combination of FTY720 plus betamethasone ointment is a promising candidate for treatment of intractable human AD.

Therapeutic approach to steroid-resistant dermatitis using novel immunomodulator FTY720 (Fingolimod) in combination with betamethasone ointment in NC/Nga mice.

The therapeutic efficacy of the novel immunomodulator FTY720 (Fingolimod), alone and in combination with betamethasone ointment, was examined in the NC/Nga mouse model of spontaneous steroid-resistant dermatitis. Male NC/Nga mice which had developed severe dermatitis were divided into six groups: 1) a biweekly betamethasone group (betamethasone ointment, twice a week), 2) a daily betamethasone group (betamethasone ointment, six times a week), 3) an FTY720 group (FTY720, orally, three times a week), 4) a biweekly combination group (oral FTY720 plus betamethasone ointment, twice a week), 5) a daily combination group (oral FTY720 plus betamethasone ointment, six times a week) and 6) a placebo group (vehicle alone). The therapeutic efficacy was evaluated in terms of severity of dermatitis, epidermal hypertrophy, accumulation and degranulation of mast cells and infiltrated CD3+ T cells into the dermis after 4 weeks of treatment. Biweekly and daily betamethasone treatments had little effect, confirming that the dermatitis was steroid-resistant. In the FTY720 and biweekly combination groups, the dermatitis showed no marked improvement. In the daily combination group, the dermatitis was significantly (p<0.05, Mann-Whitney U-test) improved as compared with the FTY720 group, biweekly and daily betamethasone groups and placebo group. Further, epidermal hypertrophy and accumulation of mast cells were suppressed. Therefore, combination therapy with FTY720 and daily betamethasone ointment is a promising candidate for treatment of steroid-resistant atopic dermatitis.

The essential structures of ISP-I that influence serine palmitoyltransferase inhibition in Chinese hamster ovary cells.

We investigated the structure-activity relationship between various ISP-I (myriocin, thermozymocidin) analogous which has sphingosine-like structure and serine palmitoyltransferase (SPT) in Chinese hamster ovary (CHO) cells utilizing sphingolipid production as a marker. Our data suggest that the double bond and/or ketone group within the alkyl chain as well as the alkyl chain are necessary for ISP-I to inhibit SPT. In addition, a serine structure is necessary for SPT inhibitory activity, which confirms previous findings.

Therapeutic approach for type 1 diabetes mellitus using the novel immunomodulator FTY720 (fingolimod) in combination with once-daily injection of insulin glargine in non-obese diabetic mice.

UNLABELLED: Aims/Introduction: The therapeutic effectiveness against type 1 diabetes mellitus (DM) of the novel immunomodulator FTY720 (fingolimod), alone and in combination with insulin glargine, was examined in the non-obese diabetic (NOD) mouse model. MATERIALS AND METHODS: Female NOD mice that had developed DM spontaneously were divided into four groups: (i) an FTY720 (0.1 mg/kg, p.o., twice weekly)-treated group; (ii) an insulin glargine (1.0 IU, s.c., once daily)-treated group; (iii) a combination FTY720 + insulin glargine (0.1-1.0 IU, s.c., once daily)-treated group; and (iv) a placebo (vehicle)-treated group. Treatment was initiated at the time of onset of DM and continued for 70 days or until death. The therapeutic efficacy of FTY720, insulin glargine and FTY720 + insulin glargine was evaluated by measuring the ratio of insulin-positive ß-cells/total islet area, the extent of islet inflammation (insulitis score), blood glucose levels, and serum C-peptide levels. RESULTS: Therapeutic administration of FTY720 to NOD mice with hyperglycemia (i.e. overt DM) significantly prolonged survival (P < 0.05 vs placebo). In the placebo group, all mice died within 63 days on the onset of DM; in contrast, 45% of FTY720-treated mice survived during the observation period (up to 70 days after the onset of DM). Therapeutic administration of FTY720 in combination with insulin glargine to NOD mice with hyperglycemia further improved survival (P < 0.05) compared with either FTY720 or insulin glargine alone (i.e. 85% of FTY720 + insulin glargine-treated mice survived to the end of the observation period). The efficacy of FTY720 in combination with insulin glargine was confirmed by histochemical, immunohistochemical and endocrinologic observations. CONCLUSIONS: Combination therapy with FTY720 plus insulin glargine is a promising candidate for the treatment of DM and may allow for a reduction in the frequency of insulin self-injections. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00160.x, 2011).

Oral therapy for type 1 diabetes mellitus using a novel immunomodulator, FTY720 (fingolimod), in combination with sitagliptin, a dipeptidyl peptidase-4 inhibitor, examined in non-obese diabetic mice.

UNLABELLED: Aims/Introduction: The therapeutic effectiveness against type 1 diabetes mellitus of a novel immunomodulator, FTY720 (fingolimod), in combination with sitagliptin, a dipeptidyl peptidase-4 inhibitor, was examined in the non-obese diabetic (NOD) mouse model. MATERIALS AND METHODS: Female NOD mice that had developed type 1 diabetes mellitus spontaneously were divided into four groups according to which therapy they received: (i) FTY720 (0.1 mg/kg, orally, six times a week) plus sitagliptin (1 mg/kg, orally, six times a week); (ii) FTY720 (0.1 mg/kg, orally, six times a week); (iii) sitagliptin (1 mg/kg, orally, six times a week); and (iv) the vehicle (water) alone. Therapeutic efficacy was evaluated in terms of survival rate, ratio of insulin-positive ß-cells/total islet area, extent of islet inflammation (insulitis score) and blood-glucose level. RESULTS: The therapeutic administration of FTY720 plus sitagliptin significantly improved survival (83% at 70 days after onset, P < 0.05) compared with sitagliptin alone (17%) or vehicle alone (0%). The fasting-blood glucose level, the ratio of insulin-positive ß-cells/total islet area and the insulitis score in the surviving mice, which had been treated with FTY720 plus sitagliptin, were improved to the normal levels as in age-matched NOD mice with normoglycemia. CONCLUSIONS: Combination therapy with FTY720 and sitagliptin is a promising candidate for type 1 diabetes mellitus treatment, and might allow the treatment of type 1 diabetes mellitus with only oral agents. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2012.00218.x, 2012).

Effects of serine palmitoyltransferase inhibitor ISP-I on the stratum corneum of intact mouse skin.

Serine palmitoyltransferase (SPT) is involved in the ceramide synthesis pathway. We investigated the effects of ISP-I, a potent inhibitor of SPT, on the stratum corneum (SC) of hairless mouse skin. Application of ISP-I for one week resulted in a significant decrease in the amount of ceramide, which was associated with a decrease in SC hydration. However, there was an increase in the number of SC layers and less transepidermal water loss than control. Transmission Electron Microscopy observation revealed that the number of desmosome-like structures in the layers immediately above the stratum granulosum (SG) was significantly increased in ISP-I-treated skin compared to vehicle-treated skin. The activity of serine protease-an enzyme associated with the process of desquamation-was lower in the SC of ISP-I-treated skin than control. Furthermore, immunoelectronmicroscopy revealed that glucosylceramide and corneodesmosin tended to remain in corneocytes and were not secreted into the intercellular spaces of the SC in the ISP-I-treated skin. These results indicate that the application of ISP-I decreases ceramide and skin hydration, while at the same time increases the number of SC layers. The accumulation of corneocyte layers may originate from an aberrant desquamation process related to the decrease in the serine protease activity as well as an alteration in the transport of desquamation-related proteases by lamellar bodies.

Relapse of experimental autoimmune encephalomyelitis after discontinuation of FTY720 (Fingolimod) treatment, but not after combination of FTY720 and pathogenic autoantigen.

FTY720 (Fingolimod) is known to have a significant therapeutic effect on experimental autoimmune encephalomyelitis (EAE). Here, we used an EAE mouse model, which had been established by immunizing C57BL/6J mice with a partial peptide of myelin oligodendrocyte glycoprotein (MOG35₋55), to examine the relapse of EAE upon discontinuation of treatment with FTY720 alone or in combination with MOG35₋55. Relapse was confirmed to occur in all animals (n=6) within one week after discontinuation of FTY720, with increase in the number of lymphocytes infiltrating the spinal cord and demyelination. However, in the case of combination therapy with FTY720 and MOG35₋55, relapse following discontinuation of treatment was completely suppressed. The autoantigenic peptide might serve to suppress the clonal selection of relapse-associated autoantigen-specific T cells.

The effects of serine palmitoyltransferase inhibitor, ISP-I, on UV-induced barrier disruption in the stratum corneum.

We examined the effects of ISP-I (myriocin, thermozymocidin) - a potent inhibitor of serine palmitoyltransferase (SPT) which is involved in the ceramide synthetic pathway-on skin barrier function in post-UVB-irradiated hairless mouse skin. Disruption of the skin barrier function after UVB irradiation as represented by the increase in transepidermal water loss (TEWL) was significantly suppressed with ISP-I treatment. In the ISP-I-treated skin, the peak of cell proliferation was observed 24 h earlier than in vehicle-treated skin. In addition, the number of apoptotic cells in ISP-I-treated skin showed a sharp decrease at 48 and 72 h post-irradiation. The number of stratum corneum cell layers was increased in ISP-I-treated skin at 72 h after UVB irradiation; at this time, TEWL in ISP-I-treated skin was lower than that in the vehicle-treated skin. We suggest ISP-I treatment altered cell proliferation and apoptosis after UVB exposure by modulating ceramide synthesis in epidermal cells, resulting in an increase of stratum corneum layers which lessened the effects of irradiation-induced barrier disruption.

TX-2152: a conformationally rigid and electron-rich diyne analogue of FTY720 with in vivo antiangiogenic activity.

We designed FTY720 analogues with conformationally rigid and electron-rich acetylenic chains as antiangiogenic agents (the monoyne 1: TX-2148, the diyne 2: TX-2152, the triyne 3: TX-2256). Molecular orbital (MO) calculations of our designed acetylenic analogues and FTY720 showed that the localization of the lowest unoccupied MO and the highest occupied MO increased from phenyl ring to acetylenic chain compared with that of FTY720. These acetylenic analogues were synthesized from p-hydroxyphenylethanol as a starting material. The construction of the acetylenic chain was carried out by an iterative strategy using a Sonogashira cross-coupling reaction and desilylative bromination in two steps. The corresponding overall yields of the monoyne 1, the diyne 2, and the triyne 3 were 27% (11 steps), 13% (13 steps), and 10% (15 steps). The in vivo antiangiogenic activities of these acetylenic analogues and FTY720 were evaluated by the chick embryo chorioallantoic membrane (CAM) assay and compared to the activities of the known antiangiogenic agent TNP-470. The diyne 2 showed more potent antiangiogenic activity (90% inhibition) than FTY720 (77% inhibition) and other acetylenic analogues (the monoyne 1: 42% inhibition, the triyne 3: 60% inhibition), and TNP-470 (82% inhibition) at a dose of 10 microg/CAM, without showing toxicity. The diyne 2 also had potent inhibitory activity at a dose of 5 and 2.5 microg/CAM. These results indicate that the flexibility of C8 alkyl chain of FTY720 is not required for its antiangiogenic activity. We suggest that the diyne 2 (TX-2152) may be a promising candidate as an antiangiogenic agent for antineoplastic drug discovery.

Preparation and antitussive, expectorant, and antiasthmatic activities of verticinone's derivatives.

To prepare verticinone derivatives with significant antitussive, expectorant, and antiasthmatic activities, the compounds 3beta-acetylverticinone (1), 3-ketoverticinone (2), 3beta-benzoylverticinone (3), 3beta-propionylverticinone (4), 3beta-butyrylverticinone (5), and 3beta-butoxycarbonylverticinone (6) have been prepared. All of these are new compounds. Among them, 1-6 exhibited potent antitussive and expectorant activities; 1 and 3-6 displayed various antiasthmatic activities. The antitussive activity of 1-6, the expectorant activity of 1-2 and 4-6, and the antiasthmatic activity of 1 are higher than those of verticinone. The results demonstrated that 1 had dominant biological activities, suggesting that it would be a potential antitussive, expectorant, and antiasthmatic agent.

Effects of phosphorylation of immunomodulatory agent FTY720 (fingolimod) on antiproliferative activity against breast and colon cancer cells.

FTY720 (fingolimod), a novel immunosuppressant, was found to become biologically activated by phosphorylation into FTY720-1-phosphate (FTY720-P), which is a high-affinity agonist for sphingosine-1-phosphate (sphingosine-1-P)-receptors. FTY720 has also been reported to have a strong antitumor activity. The association between the phosphorylation of FTY720 and the growth inhibition of FTY720 against cancer cells are still not completely understood. In this study, we investigated the effects of FTY720, sphingosine, and their related compounds on the proliferation of human breast cancer cell lines (MCF-7, MDA-MB-231 and Sk-Br-3) and human colon cancer cell lines (HCT-116 and SW620). Non-phosphorylated FTY720, sphingosine and an FTY720 derivative, ISP-I-55, showed significant growth inhibition against these cells, with IC50 values of 5-20 microM at 48 h post-drug treatment. We confirmed that FTY720 induces the activation of a major mitogen-activated protein kinase, JNK, without the activation of p38 and down-regulation of phospho-ERK in MCF-7 breast cancer cells. In contrast, the phosphorylated derivatives, FTY720-P and sphingosine-1-P, as well as a phosphinane FTY720 derivative, cFTY720-P, did not inhibit the growth of the cells in the concentration range of 5-50 microM, whereas FTY720-P and sphingosine-1-P slightly induced the growth of MCF-7 cells. Combining FTY720 with dimethylsphingosine, a sphingosine kinase inhibitor, augmented the inhibitory effect of FTY720. These results indicate that the antiproliferative activity of FTY720 does not result from its phosphorylation, either endogenous or exogenous.

Synthesis of the key intermediate, diethyl 2-acetylamino-2-(2-(4-octanoylphenyl)ethyl)propane-1,3-dioate, of the immunomodulatory agent FTY720 (fingolimod).

The key intermediate, diethyl 2-acetylamino-2-(2-(4-octanoylphenyl)ethyl)propane-1,3-dioate (13), for the immunomodulatory agent FTY720 (2: fingolimod) was synthesized via Michael addition of diethyl(acetylamino)malonate (6) to 4-octanoylstyrene (12).

Preparation of antibodies against a novel immunosuppressant, FTY720, and development of an enzyme immunoassay for FTY720.

FTY720 (1) is a novel immunosuppressant (immunomodulator), derived from ISP-I (2: myriocin and thermozymocidin). To clarify the pharmacokinetic properties of 1, antibodies against 1 were prepared and a competitive enzyme immunoassay (EIA) was developed. Two kinds of haptens, 3 and 4, for 1 were synthesized and coupled to ovalbumin (OVA). Rabbits were immunized with 3-OVA or 4-OVA, and corresponding antibodies were obtained. Both antibodies recognized the 2-amino-2-(2-phenylethyl)propane-1,3-diol moiety in 1. Using the anti-3-OVA antibody, a competitive EIA for 1 was developed and evaluated. The range of quantification by the EIA was 0.06-10 ng/mL. The application of the EIA has enabled us to measure the FTY720 concentration in serum after oral administration of 1 (1mg/kg) to rats.

A novel immunomodulator, FTY720, prevents development of experimental autoimmune myasthenia gravis in C57BL/6 mice.

Prophylactic oral administration of a novel immunomodulator (immunosuppressant), FTY720 (1 mg/kg, three times a week), completely prevented the development of experimental autoimmune myasthenia gravis (EAMG) in C57BL/6 mice. EAMG has been used as an animal model for human myasthenia gravis, and was established by immunizing the mice with acetylcholine receptor (AChR) from Torpedo californica. FTY720 also suppressed the production of both anti-Torpedo californica AChR antibody and anti-mouse AChR autoantibody by the mice, which were observed in mice in which EAMG had become established. These results strongly suggest that FTY720 is a promising candidate for treatment of human myasthenia gravis.