Ursodeoxycholic acid-2,2,4,4-d4 is the deuterated form of Ursodeoxycholic acid. Ursodeoxycholic acid is a secondary bile acid produced by the conversion of (cheno) deoxycholic acid by intestinal bacteria. It is a key regulator of intestinal barrier integrity and is essential for lipid metabolism. Ursodeoxycholic acid works as a signaling molecule by interacting with bile acid-activated receptors such as G protein-coupled bile acid receptor 5 (TGR5, GPCR19) and farnesoid X receptor (FXR). Ursodeoxycholic acid may be utilized in the research of a variety of liver and gastrointestinal diseases. Ursodeoxycholic acid also reduces ACE2 expression, helping to reduce SARS-CoV-2 infection.

Physicochemical Properties

Molecular Formula	C24H36D4O4
Molecular Weight	396.60
Exact Mass	396.318
CAS #	347841-46-7
PubChem CID	5645
Appearance	White to off-white solid powder
LogP	4.477
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	4
Heavy Atom Count	28
Complexity	605
Defined Atom Stereocenter Count	0
InChi Key	RUDATBOHQWOJDD-UHFFFAOYSA-N
InChi Code	InChI=1S/C24H40O4/c1-14(4-7-21(27)28)17-5-6-18-22-19(9-11-24(17,18)3)23(2)10-8-16(25)12-15(23)13-20(22)26/h14-20,22,25-26H,4-13H2,1-3H3,(H,27,28)
Chemical Name	4-(3,7-dihydroxy-10,13-dimethyl-2,3,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl)pentanoic acid
HS Tariff Code	2934.99.9001
Storage	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.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vitro	Drug compounds have included stable heavy isotopes of carbon, hydrogen, and other elements, mostly as quantitative tracers while the drugs were being developed. Because deuteration may have an effect on a drug's pharmacokinetics and metabolic properties, it is a cause for concern [1].
Toxicity/Toxicokinetics	Effects During Pregnancy and Lactation ◉ Summary of Use during Lactation Ursodiol is naturally present in human milk. Because of the low levels of ursodiol (ursodeoxycholic acid) in breastmilk after exogenous administration, amounts ingested by the infant are small and are not expected to cause any adverse effects in breastfed infants. Ursodiol has been given directly to newborns to safely and successfully treat prolonged neonatal jaundice. No special precautions are required. ◉ Effects in Breastfed Infants One breastfed (extent not stated) infant developed normally over the first 6 months of life during maternal ursodiol therapy of 750 to 1000 mg daily. Seven women who were taking ursodiol 14 mg/kg daily near term and postpartum. They reported no adverse reactions in their breastfed infants during the early postpartum period. A mother receiving oral ursodiol 250 mg 3 times daily for primary biliary cirrhosis reportedly breastfed her infant normally, although the extent and duration of breastfeeding was not stated. A woman with primary biliary cirrhosis developed severe pruritus and elevated serum bile acids 3 weeks postpartum. Ursodiol was started at a dose of 500 mg (7.5 mg/kg) daily, increasing to 1500 mg (25 mg/kg) daily over the next 8 weeks. Psychomotor development of her breastfed (extent not stated) infant was normal, and no apparent side effects were observed in the infant. A retrospective review of the medical records of pregnant patients at a hospital in Ankara, Türkiye who had a diagnosis of primary biliary cirrhosis found 8 patients who took ursodiol postpartum in doses of 13–15 mg/kg daily. “Most” of the patients breastfed their infants (extent not stated). No infant side effects were reported. A woman was breastfeeding her 8-day-old preterm infant 10 times daily for about 15 minutes each time. The infant was born by cesarean section at 34 weeks of gestation with a weight of 3600 grams. She was diagnosed with cholestasis, type 1 diabetes, and hypothyroidism. She was treated with ursodiol 500 mg daily, insulin levemir and aspart, and levothyroxine. She was also taking cefuroxime, flurbiprofen, a combination of acetaminophen, propyphenazone, and caffeine. The mother took the ursodiol for a total of 12 days, cefuroxime and the analgesic combination for 10 days and flurbiprofen for 15 days. No adverse effects were noticed during the period of ursodiol treatment. Twenty nursing mothers were taking ursodiol for cholestasis in daily dosages of 500 to 1500 mg or 13 to 15 mg/kg, depending on the condition. Ursodiol was discontinued 3 days postpartum. No apparent side effects were observed in any newborn infant based on standard clinical examination during early postnatal period, and no deterioration in postnatal development was observed during routine 1-year follow-up on routine pediatric examinations. ◉ Effects on Lactation and Breastmilk Relevant published information was not found as of the revision date.
References	[1]. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019;53(2):211-216. [2]. Influence of ursodeoxycholic acid on the mortality and malignancy associated with primary biliary cirrhosis: a population-based cohort study. Hepatology. 2007 Oct;46(4):1131-7. [3]. Use of ursodeoxycholic acid in liver diseases. J Gastroenterol Hepatol. 2001 Jan;16(1):3-14. [4]. Specific Bile Acids Inhibit Hepatic Fatty Acid Uptake in Mice. Hepatology. 2012 Oct;56(4):1300-10. [5]. FXR inhibition may protect from SARS-CoV-2 infection by reducing ACE2. Nature. 2022 Dec 5.
Additional Infomation	3,7-Dihydroxycholan-24-oic acid has been reported in Anser anser with data available.

Solubility Data

Solubility (In Vitro)

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

Solubility (In Vivo)

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. Injection Formulations (e.g. IP/IV/IM/SC) 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). 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) Oral Formulations 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). 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 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.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.5214 mL	12.6072 mL	25.2143 mL
	5 mM	0.5043 mL	2.5214 mL	5.0429 mL
	10 mM	0.2521 mL	1.2607 mL	2.5214 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.