FPR-1 (formyl peptide receptor 1)

Cyclosporin H is a potent marker of formyl-Met-Leu-Phe (FMLP)-induced superoxide label (O2-) formation in human neutrophils. Cyclosporin H inhibits the binding of FMLP on the HL-60 membrane, with a Ki of 0.1. Cyclosporine H inhibits the high-affinity GTPase (heterotrimer regulates the enzymatic activity of the guanine inhibitory binding protein α subunit) on the HL-60 membrane. For activation, Ki is 0.79 μM. Cyclosporine H inhibits the stimulating effect of FMLP on cytoplasmic Ca2+ concentration ([Ca2+]i), O2- formation and β-aldase release, with Ki values of 0.08, 0.24 and 0.45 μM respectively [2].

Cyclosporine H (5 mg/kg; intraperitoneally; before LPS or HCl challenge) reduces LPS or HCl-conducted lung injury (a model of lung injury) [1].

The cyclic undecapeptide, cyclosporin (Cs) H, is a potent inhibitor of FMLP-induced superoxide anion (O2-) formation in human neutrophils. We studied the effects of CsH in comparison with those of N-t-butoxycarbonyl-L-phenylalanyl-L-leucyl-L-phenylalanyl-L-leucyl-L- phenylalanine (BocPLPLP), a well known formyl peptide receptor antagonist, and of other Cs on activation of N6,2'-O-dibutyryl adenosine 3:5'-monophosphate-differentiated HL-60 cells and human erythroleukemia cells (HEL cells). CsH inhibited FMLP binding in HL-60 membranes with a Ki (inhibition constant) of 0.10 microM. CsH inhibited activation by FMLP of high affinity GTPase (the enzymatic activity of alpha-subunits of heterotrimeric regulatory guanine nucleotide-binding proteins) in HL-60 membranes with a Ki of 0.79 microM. CsH inhibited the stimulatory effects of FMLP on cytosolic Ca2+ concentration ([Ca2+]i), O2- formation, and beta-glucuronidase release with Ki values of 0.08, 0.24, and 0.45 microM, respectively. BocPLPLP was 14-fold less potent than CsH in inhibiting FMLP binding and 4- to 6-fold less potent than CsH in inhibiting FMLP-induced GTP hydrolysis, rises in [Ca2+]i, O2- formation, and beta-glucuronidase release. CsA reduced FMLP-induced O2- formation by 20%, but CsB, CsC, CsD, and CsE did not. CsA, CsB, CsC, CsD, and CsE did not affect FMLP-induced rises in [Ca2+]i. BocPLPLP inhibited leukotriene B4-induced rises in [Ca2+]i with a Ki of 0.33 microM, whereas CsH showed no inhibitory effect. CsH and BocPLPLP did not inhibit the rises in [Ca2+]i induced by several other stimuli in HL-60 cells and HEL cells. Our results show that 1) CsH is a more potent formyl peptide receptor antagonist than BocPLPLP; 2) unlike BocPLPLP, CsH is selective; and 3) N-methyl-D-valine which is present at position 11 of the amino acid sequence of CsH but not of other Cs is crucial for FMLP antagonism[2].

Cell culture and stimulation.[1]
Human alveolar epithelial cell line A549 cells were obtained from the American Type Culture Collection and were incubated in collagen-coated flasks in Roswell Park Memorial Institute (RPMI)-1640 supplemented with 10% fetal calf serum and 1% penicillin-streptomycin. AECIIs were cultured in DMEM supplemented with 10% FBS and 1% penicillin-streptomycin. All cells were incubated under the condition of 5% CO2 at 37°C. Cells were treated with indicated concentration of MTDs or fMLP for 4 h or 24 h. To investigate the role of FPR-1, the cells were preincubated with 1 µM of CsH for 30 min. To explore the signaling pathways, the cells were pretreated with 10 μM of SB203580 (p38 inhibitor), 10 μM of U0126, 10 μM of SP600125, or 5 μM of MK-2206 for 1 h.

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Cell immunofluorescence.[1]
For cell immunofluorescence, AECII were washed twice with PBS and fixed with 4% polyformaldehyde for 15 min at room temperature. After being washed with PBS three times and blocked with 1% BSA and 22.52 mg/ml of glycine in PBST (PBS+ 0.1% Tween 20) for 60 min, cells were incubated with primary anti-FPR-1 antibody (1:400; no. ab101701; Abcam) overnight at 4°C. Then, cells were washed with PBS and incubated with secondary Alexa Fluor 488 conjugated anti-rabbit antibody for 2 h, followed by incubation with DAPI for 1 min in the dark. After being washed with PBS, cells were immediately examined using fluorescence microscopy.

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Detection of IL-8.[1]
The supernatants of AECII and A549 cells were collected and centrifuged at 200 g for 5 min. Concentrations of rat CINC-1 (rat homolog for human IL-8) in AECII supernatant and human IL-8 in A549 cell supernatant were detected by commercial ELISA kit according to the manufacturer’s instruction.

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Western blot analysis.[1]
Lung tissues were collected and homogenized at 6 h after challenge. Cells were washed twice with cold PBS. Total proteins were extracted using lysis buffer containing of RIPA, protein phosphatase inhibitor cocktail, and PMSF. Whole lysates were collected and centrifuged at 1,2000 rpm at 4°C for 20 min. Protein concentrations were detected using BCA Protein Assay. Then the lysates were loaded on sodium dodecyl SDS-PAGE with 10% running gel and transferred onto PVDF membranes. Five percent BSA was used to block the membranes for 2 h. Then, the membranes were incubated with primary antibodies to FPR-1 (1:500; no. ab101701) from Abcam, and phospho-p38 mitogen-activated protein kinase (MAPK; 1:1,000; no. 4511), p38 MAPK (1:1,000; no. 8690), phospho-ERK MAPK (1:1,000; no. 4370), ERK MAPK (1:1,000; no. 4695), phospho-JNK MAPK (1:500; no. 4668), JNK MAPK (1:500; no. 9252), phospho-AKT (1:2,000; no. 4060), AKT (1:1,000; no. 4691), phospho-NF-κB p65 (1:1,000; no. 3033), and β-actin (1:2,000; no. 4970)y, overnight at 4°C and washed with TBST three times for 5 min each followed by incubation in secondary antibody for 2 h. After being washed with TBST, the loaded proteins were visualized by enhanced chemiluminescence reagents

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Specific-pathogen-free male BALB/c mice (6–8 wk of age; 18–22 g body wt) were purchased from the Model Animal Research Center of Nanjing University. The mice were housed in individually ventilated cages (5 mice/cage) supplied with filtered air and had free access to sterile water and rodent chow at 23 ± 2°C on a 12-h:12-h light-dark cycle. Animal care, handling, and experimental protocols complied with the guidelines of the Association for Assessment and Accreditation of Laboratory Animal Care International and were approved by the Animal Welfare and Use Committee of Sichuan University (Approval No. 2017049A). All animal studies are reported in compliance with the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines (https://www.nc3rs.org.uk/arrive-guidelines).[1]
To test our hypothesis that acute lung injury causes the release of NFPs into alveolar space and FPR1 plays a role in lung epithelial inflammation, we used two most commonly studied animal models of ALI. LPS (5 μg/g; Escherichia coli O111: B4), hydrochloric acid (2 μl/g; 0.1 N HCl, pH 1.5), or saline as a control was intratracheally administered in mice using a MicroSprayer as previously described by us. Cyclosporin H (CsH; Axxora platform; dissolved in ethanol and diluted by saline), a selective and potent inhibitor of FPR-1, was given by intraperitoneal injection (5 mg/kg) 1 h before LPS or HCl challenge. To thoroughly explore the direct effects of MTDs and NFP in lung injury, mice were randomly divided into six groups (n = 4–6/group at each time point): control group (MTDs/fMLP) receiving HBSS intratracheally, CsH group receiving 2 mg/kg of CsH by tail vein, MTDs group receiving MTDs intratracheally equivalent to the dose isolated from 2.5% liver, MTDs + CsH group receiving CsH 1 h before the stimulation of MTDs, fMLP group receiving 20 μM of fMLP (100 μl; Sigma) intratracheally, and fMLP + CsH group receiving CsH 1 h before the stimulation of fMLP. Mice were anesthetized intraperitoneally with 3% sodium pentobarbital (60 mg/kg) and were intratracheally exposed to the indicated substance during inspiration. All mice revived within 1 h and then returned to cages with food and water.[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.
Following oral admin of cyclosporine, the time to peak blood concns is 1.5-2.0 hr. Admin with food both delays & decreases absorption. High & low fat meals consumed within 30 min of admin decr the AUC by approx 13% & the max concn by 33%. This makes it imperative to individualize dosage regimens for outpatients. Cyclosporine is distributed extensively outside the vascular compartment. After iv dosing, the steady-state volume of distribution has been reported to be as high as 3-5 liters/kg in solid-organ transplant recipients. Only 0.1% of cyclosporine is excreted unchanged in urine. ... Cyclosporine & its metabolites are excreted principally through the bile into the feces, with only approx 6% being excreted in the urine. Cyclosporine also is excreted in human milk.
... Absorption of cyclosporine is incomplete following oral admin. The extent of absorption depends upon several variables, including the individual patient & formulation used. The elimination of cyclosporine form the blood is generally biphasic, with a terminal half-life of 5-18 hr. After iv infusion, clearance is approx 5-7 ml/min/kg in adult recipients of renal transplants, but results differ by age & patient populations. For example, clearance is slower in cardiac transplant patients & more rapid in children. The relationship between admin dose & the area under the plasma concn-vs-time curve is linear within the therapeutic range, but the intersubject variability is so large that individual monitoring is required.
Clinicians can administer cyclosporine by continuous iv infusion during the first few days after transplantation, then orally by twice-daily doses, to achieve plasma cyclosporine concns (measured by HPLC) of 75-150 ng/ml (equivalent to whole blood cyclosporine concns of 300-600 ng/ml measured by radioimmunoassay). It appears safe to maintain a trough plasma cyclosporine concn of about 75-150 ng/ml; however, this does not necessarily guarantee safety from nephrotoxicity. Because of preferential distribution of cyclosporine & its metabolites into red blood cells, blood levels are generally higher than plasma levels. When blood cyclosporine levels are 300-600 ng/ml by radioimmunoassay, cerebrospinal fluid levels range from 10-50 ng/ml. The apparent volume of distribution in children under 10 yr of age is about 35 l/kg, & in adults, 4.7 l/kg.
The elimination half-life of an oral cyclosporine dose of 350 mg is 8.9 hr; after a 1400 mg dose, the half-life is 11.9 hr. Elimination occurs predominantly by metab in the liver to form 18-25 metabolites. Metabolites of cyclosporine possess little immunosuppressive activity. Cyclosporine is extensively metabolized in the liver by cytochrome P450IIIA oxidase; however, neurotoxicity & possibly nephrotoxoicity usually correlate with raised blood levels of cyclosporine metabolites. Only 0.1% of a dose ix s excreted unchanged.
For more Absorption, Distribution and Excretion (Complete) data for CYCLOSPORIN A (7 total), please visit the HSDB record page.

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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.
Cyclosporine is extensively metabolized in the liver by the cytochrome-P450 3A (CYP3A) enzyme system & to a lesser degree by the GI tract & kidneys. At least 25 metabolites have been identified in human bile, feces, blood, & urine. Although the cyclic peptide structure of cyclosporine is relatively resistant to metab, the side chains are extensively metabolized. All of the metabolites have both reduced biological activity & toxicity compared to the parent drug.

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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.

Hepatotoxicity
In several large clinical trials, initiation of cyclosporine therapy was associated with mild elevations in serum bilirubin levels, often without significant increases in serum ALT or alkaline phosphatase. Elevations in serum enzymes were also described, but less commonly. Recently, these complications appear to be less frequent, perhaps because of more careful dosing and monitoring of cyclosporine levels. Furthermore, in treatment of autoimmune diseases without the many complications of transplantation, cyclosporine therapy has been associated with mild serum alkaline phosphatase elevations in up to 30% of patients, but the abnormalities are asymptomatic, usually self-limiting and rarely require dose adjustment. In several case series, cyclosporine therapy has also been associated with biliary sludge and cholelithiasis. Isolated case reports of clinically apparent acute liver injury have been attributed to cyclosporine. The time to onset was within a few weeks of starting cyclosporine and the pattern of serum enzyme elevations was cholestatic. Recovery was prompt once cyclosporine was stopped and cases of chronic hepatitis or acute liver failure due to cyclosporine have not been reported.
Likelihood score: C (probable rare cause of clinically apparent liver injury).

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Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Cyclosporine levels vary considerably in several case reports and series. This variability seems to be partially due to inconsistent sampling times among the reports and probably related to the fat content of the milk at the time of sampling. With typical maternal cyclosporine blood levels, a completely breastfed infant would usually receive no more than about 2% of the mother's weight-adjusted dosage or pediatric transplantation maintenance dosage, and often less than 1%. In most breastfed infants, cyclosporine is not detectable in blood; however, occasionally infants have had detectable blood levels, even when milk levels and infant dosage were apparently low.
Numerous infants have been breastfed during maternal cyclosporine use, usually with a concurrent corticosteroid and sometimes with concurrent azathioprine. At least 2 mothers successfully breastfed a second infant after successfully breastfeeding the first infant. No reports of adverse effects on infants’ growth, development or kidney function have been reported, although thorough follow-up examinations have not always been performed or reported. United States and European expert guidelines, the National Transplantation Pregnancy Registry and other experts consider cyclosporine use to be acceptable during breastfeeding, Breastfed infants should be monitored if this drug is used during lactation, possibly including measurement of serum levels to rule out toxicity if there is a concern.
Because absorption from the eye is limited, ophthalmic cyclosporine would not be expected to cause any adverse effects in breastfed infants. To substantially diminish the amount of drug that reaches the breastmilk after using eye drops, place pressure over the tear duct by the corner of the eye for 1 minute or more, then remove the excess solution with an absorbent tissue.
◉ Effects in Breastfed Infants
One infant was breastfed and follow-up showed that the infant remained healthy and normal.
A mother who was taking cyclosporine 3 mg/kg twice daily completely breastfed her infant until weaning with partial breastfeeding until 14 months. The infant's kidney function was stable and she was healthy at 2 years of age. This mother also breastfed a second infant.
In 7 infants breastfed for 4 to 12 months during maternal cyclosporine and prednisolone (plus azathioprine in 6 of the 7), infant renal function was unaffected, and they grew normally.
One mother partially breastfed her infant during cyclosporine, azathioprine and prednisone use. No follow-up data were reported.
One infant was exclusively breastfed for 10.5 months during maternal use of cyclosporine 300 mg twice daily, azathioprine and prednisone. Partial breastfeeding continued for 2 years. The infant thrived with normal growth at 12 months. The mother also breastfed a second child while on the same drug regimen.
Four infants breastfed during maternal cyclosporine use. In three, no adverse effects were noted clinically on follow-up and one of these had normal serum creatinine and urea nitrogen (BUN) measured. No follow-up was reported on the fourth infant.
Two cases were reported of infants whose mothers were taking cyclosporine and breastfeeding. One mother was taking cyclosporine 200 mg daily as well as azathioprine, prednisone, diltiazem, and folate. The second mother was taking cyclosporine 120 mg daily as well as methyldopa, prednisone, and calcitriol. Both mothers exclusively breastfed their infants initially and continued for 5 and 14 months, respectively. The infants were reportedly healthy and had normal renal function.
A woman with severe ulcerative colitis during pregnancy received cyclosporine 5 mg/kg daily from 26 weeks of pregnancy and continued while breastfeeding. She extensive breastfed her infant and at 3 months of age the infant was healthy.
The National Transplantation Pregnancy Registry reported data gathered from 1991 to 2011 on mothers who breastfed their infants following organ transplantation. A total of 43 mothers with transplants (mostly kidney) used cyclosporine while breastfeeding a total of 49 infants. Duration of nursing ranged from 1 week to 2 years and follow-up of the children ranged from weeks to 16 years. One infant experienced mildly elevated platelet count and an abnormal albumin/globulin ratio for age; at 16 months, laboratory values were normal. There were no reports of problems in the remainder of the infants or children. As of December 2013, a total of 43 mothers had breastfed 55 infants for as long as 24 months with no apparent adverse effects in infants.
A woman took cyclosporine 200 mg daily for psoriasis while exclusively breastfeeding her infant for 6 months. At 12 months of age, the infant was developing normally and had no discernible adverse effects from the drug in milk.
A woman with nephrotic syndrome took cyclosporine, prednisone, and hydroxychloroquine during pregnancy and lactation. While breastfeeding she took cyclosporine 125 mg in the morning and 100 mg at night (total of 3 mg/kg daily), hydroxychloroquine 200 mg daily and prednisone 30 mg daily. Her twin infants began partially breastfeeding (70 to 80% breastmilk) on day 7 postpartum and she continued to breastfeed for several months. The infants gained weight normally at one month of age and had no adverse reactions in the first three months postpartum.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
About 50% of the administered dose is taken up by erythrocytes while about 34% is bound to lipoproteins. Prescribing information for Sandimmune states that 90% is mainly bound to lipoproteins.

[1]. Mitochondrial peptides cause proinflammatory responses in the alveolar epithelium via FPR-1, MAPKs, and AKT: a potential mechanism involved in acute lung injury. Am J Physiol Lung Cell Mol Physiol. 2018;315(5):L775-L786.

[2]. Cyclosporin H is a potent and selective formyl peptide receptor antagonist. Comparison with N-t-butoxycarbonyl-L-phenylalanyl-L-leucyl-L-phenylalanyl-L- leucyl-L-phenylalanine and cyclosporins A, B, C, D, and E. J Immunol. 1993;150(10):4591-4599.

Cyclosporin a appears as white prismatic needles (from acetone) or white powder. (NTP, 1992)
Cyclosporine is a calcineurin inhibitor known for its immunomodulatory properties that prevent organ transplant rejection and treat various inflammatory and autoimmune conditions. It is isolated from the fungus Beauveria nivea. Initially manufactured by Sandoz and approved for use by the FDA in 1983, cyclosporine is now available in various products by Novartis (previously known as Sandoz).
Cyclosporine is a calcineurin inhibitor and potent immunosuppressive agent used largely as a means of prophylaxis against cellular rejection after solid organ transplantation. Cyclosporine therapy can be associated with mild elevations in serum bilirubin and transient serum enzyme elevations, and to rare instances of clinically apparent cholestatic liver injury.
Cyclosporine has been reported in Mycale hentscheli and Tolypocladium inflatum with data available.
Cyclosporine is a natural cyclic polypeptide immunosuppressant isolated from the fungus Beauveria nivea. The exact mechanism of action of cyclosporine is not known but may involve binding to the cellular protein cytophilin, resulting in inhibition of the enzyme calcineurin. This agent appears to specifically and reversibly inhibit immunocompetent lymphocytes in the G0-or G1-phase of the cell cycle. T-lymphocytes are preferentially inhibited with T-helper cells as the primary target. Cyclosporine also inhibits lymphokine production and release. (NCI04)
A cyclic undecapeptide from an extract of soil fungi. It is a powerful immunosupressant with a specific action on T-lymphocytes. It is used for the prophylaxis of graft rejection in organ and tissue transplantation. (From Martindale, The Extra Pharmacopoeia, 30th ed).
See also: Cyclosporin H (annotation moved to).

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Drug Indication
Cyclosporine is approved for a variety of conditions. Firstly, it is approved for the prophylaxis of organ rejection in allogeneic kidney, liver, and heart transplants. It is also used to prevent bone marrow transplant rejection. For the above indications, cyclosporine can be used in conjunction with azathioprine and corticosteroids. Finally, cyclosporine can be used in patients who have chronic transplant rejection and have received previous immunosuppressive therapy and to prevent or treat graft-versus-host disease (GVHD). Secondly, cyclosporine is used for the treatment of patients with severe active rheumatoid arthritis (RA) when they no longer respond to methotrexate alone. It can be used for the treatment of adult non-immunocompromised patients with severe, recalcitrant, plaque psoriasis that have failed to respond to at least one systemic therapy or when systemic therapies are not tolerated or contraindicated. The ophthalmic solution of cyclosporine is indicated to increase tear production in patients suffering from keratoconjunctivitis sicca. In addition, cyclosporine is approved for the treatment of steroid dependent and steroid-resistant nephrotic syndrome due to glomerular diseases which may include minimal change nephropathy, focal and segmental glomerulosclerosis or membranous glomerulonephritis. A cyclosporine ophthalmic emulsion is indicated in the treatment of vernal keratoconjunctivitis in adults and children. Off-label, cyclosporine is commonly used for the treatment of various autoimmune and inflammatory conditions such as atopic dermatitis, blistering disorders, ulcerative colitis, juvenile rheumatoid arthritis, uveitis, connective tissue diseases, as well as idiopathic thrombocytopenic purpura.
FDA Label

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Mechanism of Action
Cyclosporine is a calcineurin inhibitor that inhibits T cell activation. Its binding to the receptor cyclophilin-1 inside cells produces a complex known as cyclosporine-cyclophilin. This complex subsequently inhibits calcineurin, which in turn stops the dephosphorylation as well as the activation of the nuclear factor of activated T cells (NF-AT) that normally cause inflammatory reactions. NF-AT is a transcription factor that promotes the production of cytokines such as IL-2, IL-4, interferon-gamma and TNF-alpha, all of which are involved in the inflammatory process. Specifically, the inhibition of IL-2, which is necessary for T cell activation or proliferation, is believed to be responsible for cyclosporine's immunosuppressive actions. In addition to the above, the inhibition of NF-AT leads to lower levels of other factors associated with T helper cell function and thymocyte development.
Cyclosporine suppresses some humoral immunity but is more effective against T cell-dependent immune mechanisms such as those underlying transplant rejection & some forms of autoimmunity. It preferentially inhibits antigen-triggered signal transduction in T lymphocytes, blunting expression of many lymphokines, including /(interleukin-2)/ IL-2, as well as expression of antiapoptotic proteins. Cyclosporine forms a complex with cyclophilin, a cytoplasmic receptor protein present in target cells. This complex binds to calcineurin, inhibiting Ca2+ stimulated dephosphorylation of the cytosolic component of NFAT. When the cytoplasmic component of NFAT is dephosphorylated, it translocates to the nucleus, where it complexes with nuclear components required for complete T-cell activation, including transactivation of IL-2 & other lymphokine genes. Calcineurin enzymatic activity is inhibited following physical interaction with the cyclosporine/cyclophilin complex. This results in the blockade of NFAT dephosphorylation; thus, the cytoplasmic component of NFAT does not enter the nucleus, gene transcription is not activated, & the T lymphocyte fails to respond to specific antigenic stimulation Cyclosporine also increases expression of transforming growth fact /beta/ (TGF-B), a potent inhibitor of IL-2-stimulated T-cell proliferation & generation of cytotoxic T lymphocytes (CTL).
The exact mechanism of action is unknown but seems to be related to the inhibition of production and release of interleukin-2, which is a proliferative factor necessary for the induction of cytotoxic T lymphocytes in response to alloantigenic challenge, and which plays a major role in both cellular and humoral immune responses. Cyclosporine does not affect the nonspecific defense system of the most and does not cause significant myelosuppression.
The major pharmacodynamic action of cyclosporin within T cells is calcineurin inhibition. The complex cyclophilin-cyclosporin competitively binds to the Ca(2+)- & calmodulin-dependent phosphatase calcineurin which then inhibits downstream dephosphorylation & activation of NFAT(transcription factor). The greatest calcineurin inhibition is seen 1-2 hr after admin of Neoral in parallel to the highest blood concn.
Treatment of patients after organ transplantation with the immunosuppressive drug cyclosporin A (CsA) is often accompanied by impaired glucose tolerance, thus promoting the development of diabetes mellitus. ... /The authors/ show that 2-5 microM CsA diminishes glucose-induced insulin secretion of isolated mouse pancreatic islets in vitro by inhibiting glucose-stimulated oscillations of the cytoplasmic free-Ca(2+) concn [Ca(2+)](c). This effect is not due to an inhibition of calcineurin, which mediates the immunosuppressive effect of CsA, because other calcineurin inhibitors, deltamethrin & tacrolimus, did not affect the oscillations in [Ca(2+)](c) of the B-cells. The CsA-induced decr in [Ca(2+)](c) to basal values was not caused by a direct inhibition of L-type Ca(2+) channels. CsA is known to be a potent inhibitor of the mitochondrial permeability transition pore (PTP), which ... /the authors/ recently suggested to be involved in the regulation of oscillations. Consequently, CsA also inhibited the oscillations of the cell membrane potential, & it is shown that these effects could not be ascribed to cellular ATP depletion. However, the mitochondrial membrane potential Delta Psi was affected by CsA by inhibiting the oscillations in Delta Psi. ... The observed reduction in [Ca(2+)](c) could be counteracted by the K(+)(ATP) channel blocker tolbutamide, indicating that the stimulus-secretion coupling was interrupted before the closure of K(+)(ATP) channels. It is concluded that CsA alters B-cell function by inhibiting the mitochondrial PTP. This terminates the oscillatory activity that is indispensable for adequate insulin secretion. Thus, CsA acts on different targets to induce the immunosuppressive & the diabetogenic effect.
CsA increases CTGF, collagen I, & collagen III mRNA expressions in the heart. The induction of CTGF gene is mediated, at least in part, by angiotensin II.

C62H111N11O12

1202.6113

1215.857

C, 61.92; H, 9.30; N, 12.81; O, 15.96

83602-39-5

5280754

Cyclo[{Abu}-{Sar}-{N(Me)Leu}-Val-{N(Me)Leu}-Ala-{d-Ala}-{N(Me)Leu}-{N(Me)Leu}-{d-N(Me)Val}-{N(Me)Bmt(E)}]

Cyclo[{Abu}-{Sar}-{N(Me)Leu}-V-{N(Me)Leu}-A-{d-Ala}-{N(Me)Leu}-{N(Me)Leu}-{d-N(Me)Val}-{N(Me)Bmt(E)}]

White Solid powder

1.0±0.1 g/cm3

1282.0±65.0 °C at 760 mmHg

162-165ºC

729.1±34.3 °C

0.0±0.6 mmHg at 25°C

1.469

4.28

5

12

15

85

2330

0

[C@@H]([C@H]1C(=O)N[C@@H](CC)C(=O)N(C)CC(=O)N(C)[C@@H](CC(C)C)C(=O)N[C@@H](C(C)C)C(=O)N(C)[C@@H](CC(C)C)C(=O)N[C@@H](C)C(=O)N[C@H](C)C(=O)N(C)[C@@H](CC(C)C)C(=O)N(C)[C@@H](CC(C)C)C(=O)N(C)[C@H](C(C)C)C(=O)N1C)(O)[C@H](C)C/C=C/C

PMATZTZNYRCHOR-JLPRAAIDSA-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

(3R,6S,9S,12R,15S,18S,21S,24S,30S,33S)-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

Cyclosporin H; 5-(N-methyl-D-valine)-Cyclosporin A; Sandoz 37-839

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

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

DMSO: ~100 mg/mL (~83.2 mM)

Solubility in Formulation 1: 3 mg/mL (2.49 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 (2.49 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: ≥ 2.5 mg/mL (2.08 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 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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