Immunosuppressant

With an IC50 of 25 nM and at least higher than that of Ppia-/- splenocytes 10 times, cyclosporin (0-2500 nM; Ppia-/- cells) inhibits the proliferation of Ppia+/+ or Ppia+/- splenocytes to a similar extent[1]. Ppia-/-cell gene expression is inhibited by cyclosporine (0-750 nM) [1].

Cyclosporine is an immunosuppressive drug that is widely used to prevent organ transplant rejection. Known intracellular ligands for cyclosporine include the cyclophilins, a large family of phylogenetically conserved proteins that potentially regulate protein folding in cells. Immunosuppression by cyclosporine is thought to result from the formation of a drug-cyclophilin complex that binds to and inhibits calcineurin, a serine/threonine phosphatase that is activated by TCR engagement. Amino acids within the cyclophilins that are critical for binding to cyclosporine have been identified. Most of these residues are highly conserved within the 15 mammalian cyclophilins, suggesting that many are potential targets for the drug. We examined the effects of cyclosporine on immune cells and mice lacking Ppia, the gene encoding the prototypical cyclophilin protein cyclophilin A. TCR-induced proliferation and signal transduction by Ppia(-/-) CD4(+) T cells were resistant to cyclosporine, an effect that was attributable to diminished calcineurin inhibition. Immunosuppressive doses of cyclosporine failed to block the responses of Ppia(-/-) mice to allogeneic challenge. Rag2(-/-) mice reconstituted with Ppia(-/-) splenocytes were also cyclosporine resistant, indicating that this property is intrinsic to Ppia(-/-) immune cells. Thus, among multiple potential ligands, CypA is the primary mediator of immunosuppression by cyclosporine[1].

Absorption, Distribution and Excretion
The absorption of cyclosporine occurs mainly in the intestine. Absorption of cyclosporine is highly variable with a peak bioavailability of 30% sometimes occurring 1-8 hours after administration with a second peak observed in certain patients. The absorption of cyclosporine from the GI tract has been found to be incomplete, likely due to first pass effects. Cmax in both the blood and plasma occurs at approximately 3.5 hours post-dose. The Cmax of a 0.1% cyclosporine ophthalmic emulsion is 0.67 ng/mL after instilling one drop four times daily. A note on erratic absorption During chronic administration, the absorption of Sandimmune Soft Gelatin Capsules and Oral Solution have been observed to be erratic, according to Novartis prescribing information. Those being administered the soft gelatin capsules or oral solution over the long term should be regularly monitored by testing cyclosporine blood concentrations and adjusting the dose accordingly. When compared with the other oral forms of Sandimmune, Neoral capsules and solution have a higher rate of absorption that results in a higher Tmax and a 59% higher Cmax with a 29 % higher bioavailability.
After sulfate conjugation, cyclosporine remains in the bile where it is broken down to the original compound and then re-absorbed into the circulation. Cyclosporine excretion is primarily biliary with only 3-6% of the dose (including the parent drug and metabolites) excreted in the urine while 90% of the administered dose is eliminated in the bile. From the excreted proportion, under 1% of the dose is excreted as unchanged cyclosporine.
The distribution of cyclosporine in the blood consists of 33%-47% in plasma, 4%-9% in the lymphocytes, 5%-12% in the granulocytes, and 41%-58% in the erythrocytes. The reported volume of distribution of cyclosporine ranges from 4-8 L/kg. It concentrates mainly in leucocyte-rich tissues as well as tissues that contain high amounts of fat because it is highly lipophilic. Cyclosporine, in the eye drop formulation, crosses the blood-retinal barrier.
Cyclosporin shows a linear clearance profile that ranges from 0.38 to 3 Lxh/kg, however, there is substantial inter- patient variability. A 250 mg dose of cyclosporine in the oral soft gelatin capsule of a lipid micro-emulsion formulation shows an approximate clearance of 22.5 L/h.

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Metabolism / Metabolites
Cyclosporine is metabolized in the intestine and the liver by CYP450 enzymes, predominantly CYP3A4 with contributions from CYP3A5. The involvement of CYP3A7 is not clearly established. Cyclosporine undergoes several metabolic pathways and about 25 different metabolites have been identified. One of its main active metabolites, AM1, demonstrates only 10-20% activity when compared to the parent drug, according to some studies. The 3 primary metabolites are M1, M9, and M4N, which are produced from oxidation at the 1-beta, 9-gamma, and 4-N-demethylated positions, respectively.
Hepatic, extensively metabolized by the cytochrome P450 3A enzyme system in the liver. It is also metabolized in the gastrointestinal tract and kidney to a lesser degree. The metabolites are significantly less potent than the parent compound. The major metabolites (M1, M9, and M4N) result from oxidation at the 1-beta, 9-gamma, and 4-N-demethylated positions, respectively.
Route of Elimination: Elimination is primarily biliary with only 6% of the dose (parent drug and metabolites) excreted in the urine. Only 0.1% of the dose is excreted in the urine as unchanged drug.
Half Life: Biphasic and variable, approximately 7 hours (range 7 to 19 hours) in children and approximately 19 hours (range 10 to 27 hours) in adults.

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Biological Half-Life
The half-life of cyclosporine is biphasic and very variable on different conditions but it is reported in general to last 19 hours. Prescribing information also states a terminal half-life of approximately 19 hours, but with a range between 10 to 27 hours.

Toxicity Summary
Cyclosporine binds to cyclophilin. The complex then inhibits calcineurin which is normally responsible for activating transcription of interleukin 2. Cyclosporine also inhibits lymphokine production and interleukin release. In ophthalmic applications, the precise mechanism of action is not known. Cyclosporine emulsion is thought to act as a partial immunomodulator in patients whose tear production is presumed to be suppressed due to ocular inflammation associated with keratoconjunctivitis sicca.

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Toxicity Data
The oral LD₅₀ is 2329 mg/kg in mice, 1480 mg/kg in rats, and > 1000 mg/kg in rabbits. The I.V. LD₅₀ is 148 mg/kg in mice, 104 mg/kg in rats, and 46 mg/kg in rabbits.

[1]. Cyclophilin A-deficient mice are resistant to immunosuppression by cyclosporine. J Immunol. 2005 May 15;174(10):6030-8.

Pharmacodynamics
Cyclosporine exerts potent immunosuppressive actions on T cells, thereby prolonging survival following organ and bone marrow transplants. This drug prevents and controls serious immune-mediated reactions including allograft rejection, graft versus host disease, and inflammatory autoimmune disease. Some notable effects of cyclosporine are hypertrichosis, gingival hyperplasia, and hyperlipidemia. There is also some debate about this drug causing nephrotoxicity.

C62H111N11O12

1202.61

1201.841

79217-60-0

59865-13-3 (Cyclosporine A)

6435893

White to light yellow solid powder

1.0±0.1 g/cm3

1293.8±65.0 °C at 760 mmHg

148-151ºC

736.3±34.3 °C

0.0±0.6 mmHg at 25°C

1.468

3.35

5

12

15

85

2330

2

CCC1C(=O)N(CC(=O)N(C(C(=O)NC(C(=O)N(C(C(=O)NC(C(=O)NC(C(=O)N(C(C(=O)N(C(C(=O)N(C(C(=O)N(C(C(=O)N1)[C@@H]([C@H](C)C/C=C/C)O)C)C(C)C)C)CC(C)C)C)CC(C)C)C)C)C)CC(C)C)C)C(C)C)CC(C)C)C)C

PMATZTZNYRCHOR-KMSBSJHKSA-N

InChI=1S/C62H111N11O12/c1-25-27-28-40(15)52(75)51-56(79)65-43(26-2)58(81)67(18)33-48(74)68(19)44(29-34(3)4)55(78)66-49(38(11)12)61(84)69(20)45(30-35(5)6)54(77)63-41(16)53(76)64-42(17)57(80)70(21)46(31-36(7)8)59(82)71(22)47(32-37(9)10)60(83)72(23)50(39(13)14)62(85)73(51)24/h25,27,34-47,49-52,75H,26,28-33H2,1-24H3,(H,63,77)(H,64,76)(H,65,79)(H,66,78)/b27-25+/t40-,41?,42?,43?,44?,45?,46?,47?,49?,50?,51?,52-/m1/s1

30-ethyl-33-[(E,1R,2R)-1-hydroxy-2-methylhex-4-enyl]-1,4,7,10,12,15,19,25,28-nonamethyl-6,9,18,24-tetrakis(2-methylpropyl)-3,21-di(propan-2-yl)-1,4,7,10,13,16,19,22,25,28,31-undecazacyclotritriacontane-2,5,8,11,14,17,20,23,26,29,32-undecone

cyclosporine; 79217-60-0; Restasis; SangCyA; 30-ethyl-33-[(E,1R,2R)-1-hydroxy-2-methylhex-4-enyl]-1,4,7,10,12,15,19,25,28-nonamethyl-6,9,18,24-tetrakis(2-methylpropyl)-3,21-di(propan-2-yl)-1,4,7,10,13,16,19,22,25,28,31-undecazacyclotritriacontane-2,5,8,11,14,17,20,23,26,29,32-undecone; SCHEMBL4331439; SCHEMBL4454089; PMATZTZNYRCHOR-KMSBSJHKSA-N;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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