Fluoresterol  (Synonyms: 22-NBD Cholesterol)

Fluoresterol (22-NBD Cholesterol) is a cholesterol-specific fluorescent probe with cholesterol-mimicking binding properties. Fluoresterol is ineffective orally and does not cross the blood-brain barrier. Fluoresterol specifically binds to cholesterol transport-related proteins (such as ABCA1 and ABCG1) and is primarily used in cholesterol metabolism research, particularly for the visualization and quantitative analysis of cholesterol absorption, efflux, intracellular transport efficiency, and reverse cholesterol transport (RCT) processes. The commonly used concentration of Fluoresterol in in vitro experiments is 0.1-10 μM, and the commonly used dose in in vivo experiments is 5-20 mg/kg (gavage or intraperitoneal injection), with excitation/emission wavelengths of 472/540 nm. Fluoresterol can be applied to the study of cholesterol metabolism mechanisms related to hyperlipidemia, atherosclerosis, and non-alcoholic fatty liver disease (NAFLD)^[1][2].

Guide (The following is our recommended solution. This solution is merely a guideline and should be modified according to your specific needs.)
By detecting the fluorescence signal of 22-NBD Cholesterol (Fluoresterol) to reflect the cholesterol efflux efficiency, in vitro fluorescence labeling and cholesterol efflux experiments^[1]: 1. Cell preparation: Mouse macrophage RAW264.7 cells were seeded at a density of 3×10⁴ cells per well in a 96-well plate. 1% penicillin-streptomycin and 10% bovine serum-containing DMEM medium was added, and the cells were incubated in a 37°C, 5% CO₂ incubator for 16 hours. Mouse peritoneal macrophages were induced with 4% thioacetamide solution and then cultured on a 100% DMEM medium for 2 hours before being transferred to a new culture medium for another 48 hours for later use.
2. Fluorescence labeling: 0.2 mL of the labeled medium containing methyl-β-cyclodextrin, Topflour cholesterol (a fluorescent cholesterol analog) and unlabeled cholesterol was added to the RAW264.7 cells. After incubation for 6 hours, the cells were washed with DMEM medium to remove the unbound fluorescent cholesterol; the mouse peritoneal macrophages were treated using the same labeling method.
3. Drug treatment and incubation: After equilibrating the cells with DMEM medium containing 0.2% BSA for 1 hour, add DMEM medium containing apolipoprotein A1 (apoA1, 10 μg/mL), along with different concentration gradients of ethanol extract of Dianliangpi (EEDL: 100 μg/mL, 200 μg/mL, 400 μg/mL) or LXR agonist T0901317 (0.2 μM, 0.5 μM), and incubate at 37°C and 5% CO₂ for 18 hours.
4. Fluorescence Detection: Collect the cell culture supernatant, add lysis buffer to the cell layer, and incubate at room temperature for 30 minutes to prepare the cell lysate. Use an enzyme reader to detect the fluorescence intensity of the supernatant and the lysate. The excitation wavelength is 482 nm and the emission wavelength is 516 nm. Calculate the cholesterol efflux efficiency.

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

494.63

C₂₈H₃₈N₄O₄

78949-95-8

Solid

Yellow to orange

C[C@@]12[C@](CC[C@]2([H])[C@H](C)CNC3=CC=C([N+]([O-])=O)C4=NON=C34)([H])[C@@]5([H])[C@]([C@@]6(C(C[C@@H](O)CC6)=CC5)C)([H])CC1

Room temperature in continental US; may vary elsewhere.

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 6 months; -20°C, 1 month. When stored at -80°C, please use it within 6 months. When stored at -20°C, please use it within 1 month.

• [1]. Han W, et al. Danlou Recipe promotes cholesterol efflux in macrophages RAW264.7 and reverses cholesterol transport in mice with hyperlipidemia induced by P407. BMC Complement Med Ther. 2023 Dec 8;23(1):445.  [Content Brief]

  [2]. Altmann SW, et al. Niemann-Pick C1 Like 1 protein is critical for intestinal cholesterol absorption. Science. 2004 Feb 20;303(5661):1201-4.  [Content Brief]