Cyclooctadepsipeptide; anthelmintic

The semisynthetic derivative emodepside of PF1022A has a para-positional morpholine attached to each of the two D-phenyllactic acids. Emodepside works well against a range of nematodes that invade the gastrointestinal tract. In nematodes, emodepside binds to a presynaptic latrophilin receptor[1]. Emodepside causes a slow, concentration-dependent, time-dependent (20 min) hyperpolarization and increase in voltage-activated K currents. It is also sensitive to 4-aminopyridine.Emodepside inhibits the process of spiking. The ryanodine spike frequency increase between 20 and 35 minutes is significantly inhibited by emodepside, with a reduction of 9.8 spikes/min[2]. When emodepside is present, significantly elevated currents are detected without depolarization up to a 0 mV threshold and without the need for extra stimuli to fictitiously raise [Ca 2+]i levels. These new discoveries verify that emodepside directly targets Slo-1[3].

Emodepside inhibits three crucial physiological processes: feeding, reproduction, and locomotion. It does this by interfering with signaling at the neuromuscular junction on the pharynx, body-wall muscles, and egg-laying muscles[4].

The research of the class of cyclic octadepsipeptides started at the beginning of the 1990s. PF1022A, the starting material of emodepside, is a natural secondary metabolite of the fungus Mycelia sterilia, which belongs to the microflora of the leaves of Camellia japonica. PF1022A consists of four N-methyl-L-leucins, two D-Iactic acids and two D-phenyllactic acids, which build up a cyclic octadepsipeptide with an alternating L-D-L-configuration. Emodepside is a semisynthetic derivative of PF1022A, which contains a morpholine attached in para position at each of both D-phenyllactic acids. Emodepside is efficacious against a variety of gastrointestinal nematodes. Emodepside binds to a presynaptic latrophilin receptor in nematodes. The following presynaptic signal transduction occurs via activation of Gqalpha protein and phospholipase-Cbeta, which leads to mobilization of diacylglycerol (DAG). DAG then activates UNC-13 and synaptobrevin, two proteins which play an important role in presynaptic vesicle-functioning. This finally leads to the release of a currently unidentified transmitter. The transmitter (or modulator) exerts its effects at the postsynaptic membrane and induces a flaccid paralysis of the pharynx and the somatic musculature in nematodes[1].

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The cyclooctadepsipeptide emodepside and its parent compound PF1022A are broad-spectrum nematicidal drugs which are able to eliminate nematodes resistant to other anthelmintics. The mode of action of cyclooctadepsipeptides is only partially understood, but involves the latrophilin Lat-1 receptor and the voltage- and calcium-activated potassium channel Slo-1. Genetic evidence suggests that emodepside exerts its anthelmintic activity predominantly through Slo-1. Indeed, slo-1 deficient Caenorhabditis elegans strains are completely emodepside resistant. However, direct effects of emodepside on Slo-1 have not been reported and these channels have only been characterized for C. elegans and related Strongylida. Molecular and bioinformatic analyses identified full-length Slo-1 cDNAs of Ascaris suum, Parascaris equorum, Toxocara canis, Dirofilaria immitis, Brugia malayi, Onchocerca gutturosa and Strongyloides ratti. Two paralogs were identified in the trichocephalids Trichuris muris, Trichuris suis and Trichinella spiralis. Several splice variants encoding truncated channels were identified in Trichuris spp. Slo-1 channels of trichocephalids form a monophyletic group, showing that duplication occurred after the divergence of Enoplea and Chromadorea. To explore the function of a representative protein, C. elegans Slo-1a was expressed in Xenopus laevis oocytes and studied in electrophysiological (voltage-clamp) experiments. Incubation of oocytes with 1-10 µM emodepside caused significantly increased currents over a wide range of step potentials in the absence of experimentally increased intracellular Ca2+, suggesting that emodepside directly opens C. elegans Slo-1a. Emodepside wash-out did not reverse the effect and the Slo-1 inhibitor verruculogen was only effective when applied before, but not after, emodepside. The identification of several splice variants and paralogs in some parasitic nematodes suggests that there are substantial differences in channel properties among species. Most importantly, this study showed for the first time that emodepside directly opens a Slo-1 channel, significantly improving the understanding of the mode of action of this drug class[3].

RT-PCR was used to investigate expression of slo-1 and lat-1 in A. suum muscle flaps, and two-micropipette current-clamp and voltage-clamp techniques were used to record electrophysiological effects of emodepside. Key results: Expression of slo-1 and lat-1 were detected. Emodepside produced a slow time-dependent (20 min), 4-aminopyridine sensitive, concentration-dependent hyperpolarization and increase in voltage-activated K currents. Sodium nitroprusside increased the hyperpolarizations and K currents. N-nitro-L-arginine inhibited the hyperpolarizations and K currents. Phorbol-12-myristate-13 acetate increased the K currents, while staurosporine inhibited the hyperpolarizations and K currents. Iberiotoxin reduced these emodepside K currents. The effect of emodepside was reduced in Ca-free solutions. Emodepside had no effect on voltage-activated Ca currents. Conclusions and implications: Asu-slo-1 and Asu-lat-1 are expressed in adult A. suum muscle flaps and emodepside produces slow activation of voltage-activated Ca-dependent SLO-1-like K channels. The effect of emodepside was enhanced by stimulation of protein kinase C and NO pathways. The data are consistent with a model in which NO, PKC and emodepside signalling pathways are separate and converge on the K channels, or in which emodepside activates NO and PKC signalling pathways to increase opening of the K channels[2].

Emodepside, a cyclooctadepsipeptide, is a broad-spectrum anthelmintic previously shown to paralyse body wall muscle and pharyngeal muscle in the model nematode Caenorhabditis elegans. We demonstrate that wild-type C. elegans L4 are less sensitive than adults to emodepside in two independent assays of locomotor behaviour: body bend generation on agar (adult IC(50) 3.7 nM, L4 IC(50) 13.4 nM) and thrashing behaviour in liquid (thrashing behaviour as a % of controls after 1h in 10 microM emodepside: adults 16%, L4 worms 48%). We also show that continuous exposure of wild-type C. elegans to emodepside throughout the life-cycle from egg onwards, slows worm development, an effect that is emodepside concentration-dependent. The rate of worm-hatching from eggs on agar plates containing emodepside was not significantly different from controls, suggesting that it is development post-hatching rather than hatching itself that is affected by the drug. Emodepside also inhibits wild-type C. elegans egg-laying, with acute exposure to the drug at 500 nM resulting in an almost total inhibition within the first hour. However, the rate of egg production was not inhibited and therefore emodepside-treated worms became bloated with eggs, eventually rupturing. This suggests that the effect of emodepside on reproduction is not due to an inhibition of egg production but rather a paralytic effect on the egg-laying muscles. These results, when coupled with previous research, suggest that emodepside interferes with signalling at the neuromuscular junction on the body-wall muscles (Willson et al., 2003), pharynx (Willson et al., 2004) and egg-laying muscles and thus inhibits three important physiological functions: locomotion, feeding and reproduction[4].

[1]. Mechanisms of action of emodepside. Parasitol Res. 2005 Oct;97 Suppl 1:S1-10.

[2]. On the mode of action of emodepside: slow effects on membrane potential and voltage-activated currents in Ascaris suum. Br J Pharmacol. 2011 Sep;164(2b):453-70.

[3]. Characterization of the Ca2+-gated and voltage-dependent K+-channel Slo-1 of nematodes and its interaction with emodepside. PLoS Negl Trop Dis. 2014 Dec 18;8(12):e3401.

[4]. Effects of the novel anthelmintic emodepside on the locomotion, egg-laying behaviour and development of Caenorhabditis elegans. Int J Parasitol. 2007 May;37(6):627-36.

Emodepside is a cyclooctadepsipeptide consisting of D-lactoyl, N-methyl-L-leucyl, 3-[4-(4-morpholinyl)phenyl]-D-lactoyl, N-methyl-L-leucyl, D-lactoyl, N-methyl-L-leucyl, 3-[4-(4-morpholinyl)phenyl]-D-lactoyl, and N-methyl-L-leucyl residues joined in sequence to give a 24-membered macrocycle. An anthelmintic, it is used with praziquantel for the treatment and control of hookworm, roundworm and tapeworm infections in cats. It has a role as an antinematodal drug. It is a semisynthetic derivative and a cyclooctadepsipeptide.
Emodepside is an anthelmintic drug that is effective against a number of gastrointestinal nematodes, is licensed for use in cats and belongs to the class of drugs known as the octadepsipeptides, a relatively new class of anthelmintic.
See also: Emodepside; Praziquantel (component of).

C60H90N6O14

1119.3884

1118.65

C, 64.38; H, 8.10; N, 7.51; O, 20.01

155030-63-0

1610546-58-1 (with toltrazuril);155030-63-0;

6918632

White to off-white solid powder

5.219

0

16

14

80

1900

8

O1C([C@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N(C([H])([H])[H])C([C@@]([H])(C([H])([H])[H])OC([C@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N(C([H])([H])[H])C([C@@]([H])(C([H])([H])C2C([H])=C([H])C(=C([H])C=2[H])N2C([H])([H])C([H])([H])OC([H])([H])C2([H])[H])OC([C@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N(C([H])([H])[H])C([C@@]([H])(C([H])([H])[H])OC([C@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N(C([H])([H])[H])C([C@@]1([H])C([H])([H])C1C([H])=C([H])C(=C([H])C=1[H])N1C([H])([H])C([H])([H])OC([H])([H])C1([H])[H])=O)=O)=O)=O)=O)=O)=O)=O

ZMQMTKVVAMWKNY-YSXLEBCMSA-N

InChI=1S/C60H90N6O14/c1-37(2)31-47-57(71)77-41(9)53(67)61(11)50(34-40(7)8)60(74)80-52(36-44-17-21-46(22-18-44)66-25-29-76-30-26-66)56(70)64(14)48(32-38(3)4)58(72)78-42(10)54(68)62(12)49(33-39(5)6)59(73)79-51(55(69)63(47)13)35-43-15-19-45(20-16-43)65-23-27-75-28-24-65/h15-22,37-42,47-52H,23-36H2,1-14H3/t41-,42-,47+,48+,49+,50+,51-,52-/m1/s1

(3S,6R,9S,12R,15S,18R,21S,24R)-3,9,15,21-tetraisobutyl-4,6,10,16,18,22-hexamethyl-12,24-bis(4-morpholinobenzyl)-1,7,13,19-tetraoxa-4,10,16,22-tetraazacyclotetracosan-2,5,8,11,14,17,20,23-octaone

PF 1022-221; PF-1022 221; PF-1022-221; Emodepside; 155030-63-0; Emodepside [INN]; UNII-YZ647Y5GC9; emodepsida; emodepsidum; BAY 444400; BAY444400; BAY-444400; BAY 44-4400; BAY44-4400; BAY-44-4400;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : 100~120 mg/mL ( 89.33~107.20 mM )
Ethanol : ~20 mg/mL H2O :< 0.1 mg/mL

Solubility in Formulation 1: 3 mg/mL (2.68 mM) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 30.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 3 mg/mL (2.68 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 30.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 3 mg/mL (2.68 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 30.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 4: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: 3 mg/mL (2.68 mM)

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 (Please use freshly prepared in vivo formulations for optimal results.)