Sphingosine N-acyltransferase[2]

Drug compounds have included stable heavy isotopes of carbon, hydrogen, and other elements, mostly as tracers that influence measurement during the drug development process. It's possible that the pharmacokinetics and functional range of medications contribute to the concern over mutagenesis [1]. In monkey kidney cells, fumonisin B1 alters gene expression and causes problems with signal transmission [2]. In LLC-PK1 renal cells, fumonisin B1 promotes sphingolipid-promoted radical annihilation and sphingosine buildup, which results in sheathing astrocyte-type DNA damage [2].

Absorption, Distribution and Excretion
Fumonisin B1 (FB1), the major compound in the fumonisin group of secondary metabolites of Fusarium moniliforme Sheldon, is associated with some human and animal diseases. After intraperitoneal dosing to rats (7.5 mg/kg), FB1 was rapidly absorbed and reached a maximum concentration in plasma within 20 min after injection. Thereafter, it underwent rapid removal from plasma, displaying a mono-exponential elimination phase that fitted a one-compartment model with a half-life of 18 min. Collection of 24- and 48-hr urine samples indicated that only 16% of the applied dose was eliminated unmetabolized in urine, all within the first 24-hr period following dosing. In contrast to this, a similar dose of FB1 given by gavage resulted in the recovery of only 0.4% of the FB1 in urine.
Fumonisin B1 (FB1), a toxic and carcinogenic secondary metabolite of the fungus Fusarium moniliforme Sheldon, was administered either by i.v. injection or by gavage to vervet monkeys (Cercopithecus aethiops). FB1 dosed by i.v. injection to two female vervet monkeys was rapidly eliminated from plasma with a mean half-life during the elimination phase of 40 min. Analysis of urine and faeces over a 5 day period after dosing gave an average 47% recovery of the dose as FB1 and its hydrolysed analogues. Two female vervet monkeys were given a single gavage dose of 14C-labelled FB1. During the subsequent 3 day period, faecal excretion of radioactivity accounted for an average of 61% of the administered dose and urinary excretion 1.2%. Residual radioactivity was recovered in low levels from skeletal muscle (1%), liver (0.4%), brain (0.2%), kidney, heart, plasma, red blood cells and bile (each 0.1%), while the contents of the intestines accounted for a further 12% of the radioactive dose. In total, 76% of the administered radioactivity was recovered. Analysis of the faeces, intestinal contents and urine indicated that over 90% of the radioactivity in these samples was due to FB1 and its hydrolysis products.
A method has been developed for the determination of fumonisin B1 (FB1) in the feces of non-human primates (vervet monkeys). The animals were dosed with 14C-labelled FB1, and the radioactive compounds in faeces were recovered by repeated extractions with 0.1 M ethylenediaminetetraacetic acid. The extracts were cleaned-up on a reversed-phase (C18) solid-phase extraction cartridge, and FB1 was determined by o-phthaldialdehyde derivatization and reversed-phase HPLC. The analytical method for the determination of FB1 in the fecal extracts was reproducible [2.6% relative standard deviation (RSD)] and accurate (recovery from spiked blank extracts of 93 +/- 2.9% RSD). Confirmation of the identification of FB1 in faeces was achieved using HPLC and thin-layer chromatography, which showed that the radioactivity extracted corresponded mainly to FB1 and a new metabolite with chromatographic properties similar to those of the mycotoxin. The new metabolite was identified by mass spectrometry and nuclear magnetic resonance spectroscopy to be an equilibrium mixture of the two structural isomers of partially hydrolysed FB1, which are formed by hydrolysis of one of the ester groups of the mycotoxin.
The mycotoxin fumonisin B1 (FB1) causes a variety of health problems in animals, while epidemiological evidence suggests it is linked to human esophageal cancer. We investigated the carry-over of FB1 into bovine milk using the isolated perfused bovine udder. Two mg of FB1 was injected into the perfusion blood of 3 udders, and milk and perfused serum levels were determined for 150 min. FB1 passed through the mammary barrier into the milk, but in such low concentrations as to present a negligible risk for consumers.

Toxicity Summary
IDENTIFICATION: Fumonisin B1 is the most prevalent of the fumonisins and produced by the fungus Fusarium moniliforme and other F. species. The pure substance is a white hygroscopic powder and is soluble in water, acetonitrile-water and methanol. The material is stable at food processing temperatures and light. Fumonisin B1 is the most common fungal metabolite associated with maize. Significant accumulation in maize occurs when weather conditions favor kernel rot. HUMAN EXPOSURE: There are no confirmed records of acute toxicity associated with this compound. Available correlation studies suggest a link between dietary exposure and esophageal cancer. Other studies are inconclusive as to the potential carcinogenicity of Fumonisin B1. ANIMAL/PLANT STUDIES: Fumonisin B1 is hepatotoxic in all animal species tested including mice, rats, equids, pigs, rabbits and non-human primates. With the exception of Syrian hamsters, embryotoxicity or teratogenicity is only observed concurrent with or subsequent to maternal toxicity. Fumonisins are nephrotoxic in pigs, rats, sheep, mice and rabbits. In rats and rabbits, renal toxicity occurs at lower doses than hepatotoxicity. The fumonisins are known to cause equine leukoencephalomalacia and porcine pulmonary edema syndrome. It is hepatocarcinogenic to male rats in one strain and nephrocarcinogenic in another strain. Fumonisin B1 is a specific inhibitor of de novo sphingolipid metabolism. This compound inhibits cell growth and causes accumulation of free sphingoid bases and alteration of lipid metabolism in animals, plants and in some yeasts such as Saccharomyces cerevisae. It did not induce gene mutations in bacteria or unscheduled DNA synthesis in primary rat hepatocytes, but induced a dose dependent increase in chromosomal aberrations at low concentrations. This compound is phytotoxic, damages cell membranes and reduces chlorophyll synthesis. This compound is poorly absorbed when dosed orally based on studies using pigs, laying hens and Vervet monkeys and it is rapidly eliminated from the plasma or circulation and recovered in the feces; biliary excretion is important; enterohepatic cycling is important in some animals. Small amounts are excreted in the urine, and some is retained in the liver and kidney.[
Fumonisins are similar in structure to the long-chain base backbones of sphingolipids, allowing it to inhibit of the biosynthesis of sphingosine and more complex sphingolipids by inhibiting the enzyme ceramide synthase. This causes the accumulation of sphinganine, sphingosine, and possibly also sphingosine 1-phosphate in cells and tissues, leading to apoptosis. Mycotoxins are often able to enter the liver and kidney by human organic anion transporters (hOATs) and human organic cation transporters (hOCTs). They can also inhibit uptake of anions and cations by these transporters, interefering with the secretion of endogenous metabolites, drugs, and xenobiotics including themselves. This results in increased cellular accumulation of toxic compounds causing nephro- and hepatotoxicity. (A704, L1937, A2947, A3014)

[1]. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019 Feb;53(2):211-220.

[2]. The toxicity of fumonisin B1, B2, and B3, individually and in combination, in chicken embryos. Poult Sci. 2001 Apr;80(4):401-7.

[3]. Effect of fumonisin B₁ on the cell cycle of normal human liver cells. Mol Med Rep. 2013 Jun;7(6):1970-6.

Fumonisin B1 can cause cancer according to The World Health Organization's International Agency for Research on Cancer (IARC) and The National Toxicology Program.
2-[2-({19-amino-6-[(3,4-dicarboxybutanoyl)oxy]-11,16,18-trihydroxy-5,9-dimethylicosan-7-yl}oxy)-2-oxoethyl]butanedioic acid is a fumonisin.
Fumonisin b1 has been reported in Fusarium fujikuroi and Streptomyces rapamycinicus with data available.
Fumonisin B1 is a mycotoxin produced by Fusarium moniliforme. It is a contaminant of cereals, especially corn. It has been epidemiologically linked to high incidence of human esophageal cancer in South Africa and China and to hepatocarcinogenesis in animal models.
Fumonisin B1 is from Fusarium moniliforme Fumonisin B1 is an inhibitor of ceramide synthase.

Fumonisin B1 belongs to the family of Monoterpenes. These are compounds contaning a chain of two isoprene units.
See also: Fumonisin B1 (annotation moved to).

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Mechanism of Action
Fumonisins are inhibitors of the biosynthesis of sphingosine and more complex sphingolipids. In eucaryotic cells, fumonisin inhibition of sphingolipid biosynthesis is a result of inhibition of the enzyme ceramide synthase. Large increase in free sphinganine concentration in plant and animal cells are observed within a few hours after exposure to fumonisins and/or Alternaria toxins (AAL-toxins). Some of the sphinganine is metabolized to other bioactive intermediates, and some is released from cells. In animals, free sphinganine accumulates in tissues and quickly appears in blood and urine. Free sphingoid bases are toxic to most cells, and complex sphingolipids are essential for normal cell growth. Fumonisin B1 stimulates sphinganine-dependent DNA synthesis in Swiss 3T3 cells, but is mitoinhibitory in other cell types. In cultured cells the accumulation of bioactive long-chain sphingoid bases and depletion of complex sphingolipids are clearly contributing factors in growth inhibition, increased cell death, and (in Swiss 3T3 cells) mitogenicity of fumonisins. While disruption of sphingolipid metabolism directly affects cells, it may indirectly affect some tissues. For example, fumonisin B1 impairs the barrier function of endothelial cells in vitro. Adverse effects on endothelial cells could indirectly contribute to the neurotoxicity and pulmonary edema caused by fumonisins. It is hypothesized that fumonisin-induced changes in the sphingolipid composition of target tissues could directly or indirectly contribute to all Fusarium moniliforme-associated diseases.
Fumonisins are inhibitors of sphinganine (sphingosine) N-acyltransferase (ceramide synthase) in vitro, and exhibit competitive-type inhibition with respect to both substrates of this enzyme (sphinganine and fatty acyl-CoA). Removal of the tricarballylic acids from fumonisin B1 reduces the potency by at least 10 fold; and fumonisin A1 (which is acetylated on the amino group) is essentially inactive. Studies with diverse types of cells (hepatocytes, neurons, kidney cells, fibroblasts, macrophages, and plant cells) have established that fumonisin B1 not only blocks the biosynthesis of complex sphingolipids; but also, causes sphinganine to accumulate. Some of the sphinganine is metabolized to the 1-phosphate and degraded to hexadecanal and ethanolamine phosphate, which is incorporated into phosphatidylethanolamine. Sphinganine is also released from cells and, because it appears in blood and urine, can be used as a biomarker for exposure. The accumulation of these bioactive compounds, as well as the depletion of complex sphingolipids, may account for the toxicity, and perhaps the carcinogenicity, of fumonisins.
Fumonisin B1 produced by the fungus Fusarium moniliforme is a member of a new class of sphinganine analogue mycotoxins that occur widely in the food chain. Epidemiological studies associate FB1 with human sophageal cancer in China and South Africa. FB1 also causes acute pulmonary edema in pigs and equine leucoencephalomalacia. This disease is thought to be a consequence of inhibition by FB1 of cellular ceramide synthesis in cells. To investigate further on this pathogenesis, the effect of FB1 was studied on cell viability (3 to 54 uM of FB1), protein (2.5 to 20 uM of FB1) and DNA syntheses (2.5 to 50 uM of FB1), and cellular cycle (3 to 18 uM of FB1) of rat C6 glioma cells after 24 hr incubation. The results of the viability test show that FB1 induces 10 2% and 47 4% cell death with, respectively, 3 and 54 uM, in C6 cells. This cytotoxicity induced by FB1 was efficiently prevented when the cells were preincubated 24 hr with vitamin E (25 uM). FB1 displays epigenetic properties since it induced hypermethylation of the DNA (9-18 uM). Inhibition of protein synthesis was observed with FB1 with an IC50 of 6 M showing that C6 glioma cells are very sensitive to FB1; however, the synthesis of DNA was only slightly inhibited, up to 20 uM of FB1. The flow cytometry showed that the number of cells in phase S decreased significantly as compared to the control p = 0.01 from 18.7 2.5% to 8.1 1.1% for 9 uM FB1. The number of cells in phase G2/uM increased significantly as compared to the control (p 0.05) from 45.7 0.4% to 54.8 1.1% for 9 uM FB1, whereas no change occurs in the number of cells in the phase G0/G1. These results show that cytotoxic concentrations of FB1 induce cellular cycle arrest in phase G2/uM in rat C6 glioma cells possibly in relation with genotoxic events.
The molecular mechanism of action of fumonisins is not known; however, these compounds bear a remarkable structural similarity to sphingosine, the long-chain (sphingoid) base backbone of sphingomyelin, cerebrosides, sulfatides, gangliosides and other sphingolipids. Sphingolipids are thought to be involved in the regulation of cell growth, differentiation and neoplastic transformation through participation in cell-cell communication and cell-substratum interactions and possibly through interactions with cell receptors and signalling systems. Incubation of rat hepatocytes with fumonisins B1 and B2 inhibited incorporation of (14)C serine into the sphingosine moiety of cellular sphingolipids, at an IC50 of 0.1 uM. In contrast, fumonisin B1 increased the amount of the biosynthetic intermediate, sphinganine, which suggests that fumonisins inhibit the conversion of (14)C-sphinganine to N-acyl-(14)C-sphinganines, a step that is thought to precede introduction of the 4,5-trans double bond of sphingosine. In agreement with this mechanism, fumonisin B1 inhibited the activity of sphingosine N-acyltransferase (ceramide synthase) in rat liver microsomes, with 50% inhibition at approximately 0.1 uM, and reduced the conversion of (3)H-sphingosine to (3)H-ceramide by intact hepatocytes. Fumonisin B1 (1 uM) almost completely inhibited (14)C sphingosine formation by hepatocytes.

13C34H59NO15

755.58

721.388

1217458-62-2

Fumonisin B1;116355-83-0

3431

Powder

2 °C

-0.5

8

16

31

50

1070

0

O([13C]([13CH2][13C@H]([13C](=O)O)[13CH2][13C](=O)O)=O)[13C@@H]([13CH2][13C@@H]([13CH3])[13CH2][13C@H]([13CH2][13CH2][13CH2][13CH2][13C@@H]([13CH2][13C@H]([13C@H]([13CH3])N)O)O)O)[13C@@H]([13C@@H]([13CH3])[13CH2][13CH2][13CH2][13CH3])O[13C]([13CH2][13C@H]([13C](=O)O)[13CH2][13C](=O)O)=O

UVBUBMSSQKOIBE-UHFFFAOYSA-N

InChI=1S/C34H59NO15/c1-5-6-9-20(3)32(50-31(44)17-23(34(47)48)15-29(41)42)27(49-30(43)16-22(33(45)46)14-28(39)40)13-19(2)12-24(36)10-7-8-11-25(37)18-26(38)21(4)35/h19-27,32,36-38H,5-18,35H2,1-4H3,(H,39,40)(H,41,42)(H,45,46)(H,47,48)

2-[2-[19-amino-6-(3,4-dicarboxybutanoyloxy)-11,16,18-trihydroxy-5,9-dimethylicosan-7-yl]oxy-2-oxoethyl]butanedioic acid

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)

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.)